Hmgb1 antagonist treatment of severe sepsis

ABSTRACT

The present invention is related to the use of HMGB1 antagonists such as K883 in the treatment and/or prevention and/or inhibition of severe sepsis in mammals, e.g., humans, and pharmaceutical compositions for the same comprising HMGB1 antagonists in an effective amount to treat and/or prevent and/or inhibit this condition.

This application claims the benefit of U.S. Provisional Application Nos.62/845,568, 62/845,576 and 62/845,578, all filed on May 9, 2019, and allhereby incorporated by reference.

FIELD OF THE INVENTION

The present invention is related to the use of HMGB1 antagonists in thetreatment and/or prevention and/or inhibition of severe sepsis inmammals, e.g., humans, and pharmaceutical compositions for the samecomprising HMGB1 antagonists in an effective amount to treat and/orprevent and/or inhibit this condition.

BACKGROUND OF THE INVENTION

High mobility group box 1 (HMGB1) was first identified as a DNA-bindingprotein; it is translocated to the nucleus in healthy cells. (Baker, C.,et al., Physical studies of the nonhistone chromosomal proteins HMG-Uand HMG-2, Biochemistry, 1976, 15(8): p. 1645-9); (Bertheloot, D, HMGB1,IL-1alpha, IL-33 and S100 proteins: dual-function alarmins, Cell MolImmunol, 2016; Tsung, A., S. Tohme, and T. R. Billiar, High-mobilitygroup box-1 in sterile inflammation, J Intern Med, 2014, 276(5): p.425-43; Lotze, M. T. and K. J. Tracey, High-mobility group box 1 protein(HMGB1): nuclear weapon in the immune arsenal, Nat Rev Immunol, 2005,5(4): p. 331-42). Cellular damage, necrosis, or apoptotic cell fragmentsresult in the passive release of HMGB1 into the extracellular space(Scaffidi, P., T. Misteli, and M. E. Bianchi, Release of chromatinprotein HMGB1 by necrotic cells triggers inflammation, Nature, 2002,418(6894): p. 191-5), which can recruit leukocytes to the site of aninjury or infection. HMGB1 can also be secreted by monocytes, tissuemacrophages, and other cell of the innate immune system when these cellsare activated by pathogen-derived stimuli, exosomes, or pro-inflammatorycytokines (Andersson, U. and K. J. Tracey, HMGB1 is a therapeutic targetfor sterile inflammation and infection, Annu Rev Immunol, 2011, 29: p.139-62; Bertheloot, D, HMGB1, IL-1alpha, IL-33 and S100 proteins:dual-function alarmins, Cell Mol Immunol, 2016). Depending upon itsoxidation state and which of the multiple distinct receptors itinteracts with, extracellular HMGB1 can trigger a variety of outcomes(reviewed in Bertheloot, D, HMGB1, IL-1alpha, IL-33 and S100 proteins:dual-function alarmins, Cell Mol Immunol, 2016 and Harris, H. E., HMGB1:a multifunctional alarmin driving autoimmune and inflammatory disease,Nat Rev Rheumatol, 2012, 8(4): p. 195-202), including secretion ofadditional HMGB1. When this feed-forward loop becomes dysregulated, asin patients with sepsis, it can create a vicious cycle that stokessystemic inflammation by activating macrophages through the TLR4receptor (Apetoh, L., et al., The interaction between HMGB1 and TLR4dictates the outcome of anticancer chemotherapy and radiotherapy,Immunol Rev, 2007, 220: p. 47-59; Apetoh, L., et al., Toll-like receptor4-dependent contribution of the immune system to anticancer chemotherapyand radiotherapy, Nat Med, 2007, 13(9): p. 1050-9; Fan, J., et al.,Hemorrhagic shock induces NAD(P)H oxidase activation in neutrophils:role of HMGB1-TLR4 signaling, J Immunol, 2007, 178(10): p. 6573-80;Tsung, A., et al., HMGB1 release induced by liver ischemia involvesToll-like receptor 4 dependent reactive oxygen species production andcalcium-mediated signaling, J Exp Med, 2007, 204(12): p. 2913-23; Tsung,A., et al., Increasing numbers of hepatic dendritic cells promoteHMGB1-mediated ischemia-reperfusion injury, J Leukoc Biol, 2007, 81(1):p. 119-28).

HMGB1 is a highly conserved protein that is central to the pathogenesisof sterile and pathogen-induced inflammation (Andersson, U., HMGB1 is atherapeutic target for sterile inflammation and infection, Annu RevImmunol, 2011, 29: p. 139-62). Lethal organ failure and epithelialbarrier failure without shock are driven by HMGB1. HMGB1 release isdriven by a positive feedback loop that causes circulating HMGB1 levelsgenerally to rise as disease progresses.

HMGB1 is a key member of the damage-associated molecule patternmolecules (DAMPs) and it therefore plays an important role in systemicinflammation and has a pathogenic role in infectious diseases like viralor bacterial infections. Virally infected or otherwise stressed cellswill release endogenous DAMPs to alarm the environment about a loss ofintracellular homeostatic balance. HMGB1 is one of the most extensivelystudied DAMPs and is involved in the pathogenesis of many inflammatorydiseases of infectious or sterile origin. (Andersson U, et al., HMGB1 isa therapeutic target for sterile inflammation and infection, Annu RevImmunol, 2011; 29:139-62; Kang R, et al., HMGB1 in health and disease).Molecular aspects of medicine, 2014; 40:1-116. HMGB1 is a ubiquitous,evolutionary extremely conserved chromatin-binding protein present inall mammalian nucleated cells plus platelets. This 25 kD protein is 99%identical in mammals. The intranuclear functions involve regulation ofgene transcription, chromatin repair, and additional tasks. HMGB1 may,in addition, be passively extracellularly released as a prototypicalDAMP from dying cells or actively secreted by stressed or activatedcells present in any tissue. (Andersson U, et. al., High-mobility groupbox 1 protein (HMGB1) operates as an alarmin outside as well as insidecells, Semin Immunol, 2018; 38:40-8). Active HMGB1 release starts with aregulated translocation of the nuclear pool of HMGB1 to the cytosol.(Bonaldi T, et al., Monocytic cells hyperacetylate chromatin proteinHMGB1 to redirect it towards secretion, The EMBO Journal, 2003;22(20):5551-60). Type 1 and type 2 interferons are highly potentendogenous molecules that initiate this intracellular relocalization ofHMGB1. (Lu B, et al., JAK/STAT1 signaling promotes HMGB1hyperacetylation and nuclear translocation, Proceedings of the NationalAcademy of Sciences of the United States of America, 2014;111(8):3068-73; Tanaka A, et al, Serum high-mobility group box 1 iscorrelated with interferon-alpha and may predict disease activity inpatients with systemic lupus erythematosus, Lupus, 2019; 28(9):1120-7).Consequently, administration of interferons as therapeutic antiviralcompounds risks to increase extracellular HMGB1 levels, which maypromote inflammation rather than mediate beneficial effects. Excessiveextracellular HMGB1 quantities cause tissue damage and organdysfunction. For example, lethality in bacterial pneumonia complicatedby ARDS was strongly predicted by initial appropriate antibiotic use andday 1 and day 3 plasma HMGB1 levels. (Tseng C C, et al, Impact of serumbiomarkers and clinical factors on intensive care unit mortality and6-month outcome in relatively healthy patients with severe pneumonia andacute respiratory distress syndrome, Disease Markers, 2014;2014:804654). Preclinical treatment with HMGB1-specific antagonistsameliorates inflammation and improves survival in many models of acuteor chronic inflammatory diseases. (Andersson U, Tracey K J, HMGB1 is atherapeutic target for sterile inflammation and infection, Annu RevImmunol, 2011; 29:139-62; Kang R, et al., HMGB1 in health and disease,Molecular Aspects of Medicine, 2014; 40:1-116; Andersson U, et al.,Extracellular HMGB1 as a therapeutic target in inflammatory diseases,Expert Opin Ther Targets, 2018; 22(3):263-77). However, therapy withHMGB1-specific antagonists has not yet been studied in clinical trials.

HMGB1 receptor usage that generates inflammation is entirely dependenton whether HMGB1 acts on its own or in complex with partner molecules.HMGB1 has a strong bipolar charge and is prone to complex-bind otherproinflammatory molecules including DNA, RNA, histones, nucleosomes,LPS, SDF-1, IL-1α, IL-1β and additional factors. (Andersson U, et al.,High-mobility group box 1 protein (HMGB1) operates as an alarmin outsideas well as inside cells, Semin Immunol, 2018; 38:40-8; Tian J, et al,Toll-like receptor 9-dependent activation by DNA-containing immunecomplexes is mediated by HMGB1 and RAGE, Nature Immunology. 2007;8(5):487-96; Huang W, et al, High-mobility group box 1 impairs airwayepithelial barrier function through the activation of the RAGE/ERKpathway, International Journal of Molecular Medicine. 2016;37(5):1189-98; Deng M, et al, The Endotoxin Delivery Protein HMGB1Mediates Caspase-11-Dependent Lethality in Sepsis, Immunity, 2018;49(4):740-53.e7; Porat A, et al., DNA-Mediated Interferon SignatureInduction by SLE Serum Occurs in Monocytes Through Two Pathways: AMechanism to Inhibit Both Pathways, Frontiers in Immunology, 2018;9:2824). The original discovery of HMGB1 was based on its ability tobind nuclear DNA. (Goodwin G H, et al., A new group ofchromatin-associated proteins with a high content of acidic and basicamino acids, European Journal of Biochemistry, 1973; 38(1):14-9). Thenumber of suggested cognate receptors for extracellular HMGB1 reportedin the literature is quite extensive. However, only two receptorsystems, the receptor for advanced glycation end products (RAGE) andtoll-like receptor 4 (TLR4), are fully confirmed to act as functionalHMGB1 receptors. (Rauvala H, Rouhiainen A, RAGE as a receptor of HMGB1(Amphoterin): roles in health and disease, Current Molecular Medicine,2007; 7(8):725-34; Yang H, et al., A critical cysteine is required forHMGB1 binding to Toll-like receptor 4 and activation of macrophagecytokine release, Proceedings of the National Academy of Sciences of theUnited States of America, 2010; 107(26):11942-7; Yang H, et al., MD-2 isrequired for disulfide HMGB1-dependent TLR4 signaling, The J. Exp Med,2015; 212(1):5-14 (18-20)). Many receptor systems claimed to operate asHMGB1 receptors are actually receptors for molecules complex-bound toHMGB1.

The receptor for advanced glycation end products (RAGE) was originallyidentified in diabetes research as a cell surface receptor generating acascade of intracellular signaling, including nuclear NF-kBtranslocation and proinflammatory cytokine release. (Schmidt A M, etal., RAGE: a novel cellular receptor for advanced glycation endproducts, Diabetes, 1996; 45 Suppl 3: S77-80). It was later discoveredthat RAGE is a multiligand receptor and that HMGB1 is one out of manyligands. (Rauvala H, Rouhiainen A, RAGE as a receptor of HMGB1(Amphoterin): roles in health and disease, Current Molecular Medicine,2007; 7(8):725-34). The HMGB1-RAGE axis triggers neutrophil-mediatedinjury amplification following necrosis (Huebener P, et al., TheHMGB1/RAGE axis triggers neutrophil-mediated injury amplificationfollowing necrosis, The Journal of Clinical Investigation. 2015;125(2):539-50) something that is of great significance for thepathogenesis of acute lung injury. Interestingly, HMGB1-RAGE interactiondoes not primarily lead to proinflammatory intracellular signaling.Macrophages expressing RAGE, but engineered to lack TLR4 expression, donot produce proinflammatory cytokines in response to stimulation byHMGB1 of any redox isoform. (Yang H, et al., A critical cysteine isrequired for HMGB1 binding to Toll-like receptor 4 and activation ofmacrophage cytokine release, Proceedings of the National Academy ofSciences of the United States of America, 2010; 107(26):11942-7). Thatis not the expected result if HMGB1-RAGE interaction mediated cytokinerelease in a direct mode.

Recent observations demonstrate that RAGE provides a transport route forHMGB1 and HMGB1-partner molecule complexes by endocytosis to theendolysosomal compartment. (Deng M, et al., The Endotoxin DeliveryProtein HMGB1 Mediates Caspase-11-Dependent Lethality in Sepsis,Immunity, 2018; 49(4):740-53.e7; Porat A, et al, DNA-Mediated InterferonSignature Induction by SLE Serum Occurs in Monocytes Through TwoPathways: A Mechanism to Inhibit Both Pathways, Frontiers in Immunology,2018; 9:2824; Lin H J, et al., Coalescence of RAGE in Lipid Rafts inResponse to Cytolethal Distending Toxin-Induced Inflammation, Frontiersin Immunology, 2019; 10:109; Yang H, et al., Inhibition ofHMGB1/RAGE-mediated endocytosis by HMGB1 antagonist box A, anti-HMGB1antibodies, and cholinergic agonists suppresses inflammation, MolecularMedicine (Cambridge, Mass.), 2019; 25(1):13; Jia C, et al., Endothelialcell pyroptosis plays an important role in Kawasaki disease viaHMGB1/RAGE/cathespin B signaling pathway and NLRP3 inflammasomeactivation, Cell Death Dis, 2019; 10(10):778; Xu J, et al., Macrophageendocytosis of high-mobility group box 1 triggers pyroptosis, Cell Deathand Differentiation, 2014; 21(8):1229-39). The HMGB1/RAGE-assistedcellular import system performs an important task by alerting cellsabout a dangerous environment. Most importantly, HMGB1 has a uniqueability to act as a detergent in the lysosomal membrane due to theacidic conditions inside the lysosome system. (Deng M, et al., TheEndotoxin Delivery Protein HMGB1 Mediates Caspase-11-Dependent Lethalityin Sepsis, Immunity, 2018; 49(4):740-53.e7). The HMGB1-transportedpartner molecules will thus avoid the expected degradation in thelysosomes and instead leak out from the permeabilized lysosomes into thecytosol to reach cognate cytoplasmic receptors which will be activatedto cause inflammation. This biology may have tremendously importantconsequences for the pathogenesis of severe pulmonary inflammation. Onlytwo human organs, the lungs and skin (Shirasawa M, et al., Receptor foradvanced glycation end-products is a marker of type I lung alveolarcells, Genes to Cells: Devoted to Molecular & Cellular mechanisms, 2004;9(2):165-74; Guo W A, et al., The receptor for advanced glycation endproducts and acute lung injury/acute respiratory distress syndrome,Intensive Care Medicine. 2012; 38(10):1588-98), display a highconstitutive cell surface RAGE expression and the critical cognate HMGB1receptor RAGE is thus abundantly expressed in the lower respiratorytract. It has been demonstrated in preclinical and clinical studies thatsevere respiratory infections including influenza and human respiratorysyncytial virus (HRSV) generate a substantial extracellular HMGB1release in the inflamed lungs and that HMGB1-specific antagonistsameliorate these conditions. (Ito Y, et al, Increased levels ofcytokines and high-mobility group box 1 are associated with thedevelopment of severe pneumonia, but not acute encephalopathy, in 2009H1N1 influenza-infected children., Cytokine, 2011; 56(2):180-7; NosakaN, et al., Anti-high mobility group box-1 monoclonal antibody treatmentprovides protection against influenza A virus (H1N1)-induced pneumoniain mice, Critical Care (London, England) 2015; 19:249; Nosaka N, et al.,Anti-high mobility group box-1 monoclonal antibody treatment of brainedema induced by influenza infection and lipopolysaccharide, Journal ofMedical Virology. 2018; 90(7):1192-8; Hatayama K, et al., Combinedeffect of anti-high-mobility group box-1 monoclonal antibody andperamivir against influenza A virus-induced pneumonia in mice, Journalof Medical Virology, 2019; 91(3):361-9; Manti S, et al., Induction ofhigh-mobility group Box-1 in vitro and in vivo by respiratory syncytialvirus, Pediatr Res, 2018; 83(5):1049-56; Rayavara K, et al.,Proinflammatory Effects of Respiratory Syncytial Virus-InducedEpithelial HMGB1 on Human Innate Immune Cell Activation, J Immunol,2018; 201(9):2753-66; Rallabhandi P, et al., Respiratory syncytial virusfusion protein-induced toll-like receptor 4 (TLR4) signaling isinhibited by the TLR4 antagonists Rhodobacter sphaeroideslipopolysaccharide and eritoran (E5564) and requires direct interactionwith MD-2, mBio, 2012; 3(4); Simpson J, et al., RSV Infection PromotesNecroptosis and HMGB1 Release by Airway Epithelial Cells, AmericanJournal of Respiratory and Critical Care Medicine, 2020 (29-36)). HMGB1accumulates locally due to passive release from dying cells and activatesecretion from innate immunity cells and additional cell types.Furthermore, virus-induced cell death also generates huge quantities ofextracellular DNA, RNA, nucleosomes and histones. These molecules are ofno major concern as long as they remain extracellularly or get degradedin the lysosomes after cellular import. The potential threat is thatthese nuclear danger-molecules will get access to their cognatecytosolic pattern recognition receptors, which will fuel inflammationincluding inflammasome activation. Excessive amounts of extracellularHMGB1 and abundant cell surface RAGE expression in the tissue may enablean intracellular transport of extracellular DNA and RNA to get access totheir potent cytosolic cognate receptors cGAS, AIM2, RIG-I andadditional nucleic acid receptors with sometimes overwhelminginflammation as the end result. (Andersson U, et al., High-mobilitygroup box 1 protein (HMGB1) operates as an alarmin outside as well asinside cells, Semin Immunol, 2018; 38:40-8). See FIG. 1

FIG. 1 shows inflammation induced by HMGB1-partner molecule complexes.As seen in FIG. 1, necrotic cells release DAMP and pathogen-associatedmolecular patterns (PAMP) molecules extracellularly where they formcomplexes with HMGB1 released from dying or activated cells (1); thesecomplexes bind to RAGE abundantly expressed in the lungs (2); and getendocytosed to endosomes having TLR receptors including TLR4 which maybe activated by HMGB1 (3); HMGB1 and partner molecules translocate tolysosomes, where HMGB1 acts like a detergent under the acidic conditionsand disrupts the lysosomal membrane enabling HMGB1-partner moleculesaccess to the cytosol (4); the translocated molecules bind and activatereciprocal cytoplasmic receptors generating inflammasome activation andadditional proinflammatory events (5); the subsequent outcome productionand extracellular release of cytokines via pore formation in the cellsurface membrane accomplished by oligomerized gasdermin D. The finaloutcome is pyroptosis. Active gasdermin D also rotates and translocatesphosphatidylserine molecules to the outside of the cell surface membraneand induces tissue factor on endothelial cells. This biology initiatescoagulation (6).

The redox state of the three cysteines present in HMGB1 is key whenHMGB1 acts on its own as a pro-inflammatory DAMP. Gentle oxidationgenerating a disulfide bond between Cys23 and Cys45 with Cys106retaining its thiol group forms an HMGB1 redox isoform (disulfide HMGB1)that like lipopolysaccharide (LPS) is a potent functional TLR4 ligand.(Kang R, et al. HMGB1 in health and disease, Molecular aspects ofmedicine, 2014; 40:1-116). Disulfide HMGB1 binds at low nanomolaravidity to the TLR4 co-receptor MD-2, in an analogous way to LPS but ata different position. (Yang H, et al., MD-2 is required for disulfideHMGB1-dependent TLR4 signaling, The J Exp Med, 2015; 212(1):5-14).Disulfide HMGB1-TLR4 stimulation induces a substantial production ofproinflammatory cytokines both in vivo and in vitro. (Yang H, et al., Acritical cysteine is required for HMGB1 binding to Toll-like receptor 4and activation of macrophage cytokine release, Proceedings of theNational Academy of Sciences of the United States of America, 2010;107(26):11942-7). The clinical outcome of murine influenza infection hasbeen demonstrated to be significantly improved by TLR4-specificantagonists. A small-molecule TLR4-specific antagonist (P5779) thatselectively prevents HMGB1-MD-2 interaction, but not LPS from binding toMD-2, protected mice from influenza virus-induced lethality and reducedproinflammatory cytokine gene expression in the lungs. (Shirey K A, etal., The TLR4 antagonist Eritoran protects mice from lethal influenzainfection., Nature, 2013; 497(7450):498-502).

HMGB1/RAGE/TLR4 plays a role in the pathogenesis of severe pulmonaryinflammation. Influenza viruses cause 3-5 million severe cases and250,000-500,000 deaths worldwide annually. (Paules C, et al., Influenza,Lancet (London, England), 2017; 390(10095):697-708). These viruses, likethe SARS-CoV-2 virus, replicate in respiratory epithelial cells andcause necrotic tissue damage. Influenza-infected patients expresssubstantially increased systemic HMGB1 levels that are associated withthe development of severe pneumonia. (Ito Y, et al., Increased levels ofcytokines and high-mobility group box 1 are associated with thedevelopment of severe pneumonia, but not acute encephalopathy, in 2009H1N1 influenza-infected children, Cytokine, 2011; 56(2):180-7).

Gene-deficient TLR4 as well as gene-deficient RAGE mice are partiallyprotected from influenza-induced lethality. (van Zoelen M A, et al.,Receptor for advanced glycation end products is detrimental duringinfluenza A virus pneumonia, Virology, 2009; 391(2):265-73; Nhu Q M, etal., Novel signaling interactions between proteinase-activated receptor2 and Toll-like receptors in vitro and in vivo, Mucosal Immunology,2010; 3(1):29-39). Successful preclinical treatment results usingspecific HMGB1-, TLR4- or RAGE-antagonists further support that theHMGB1/RAGE/TLR4-axis is central in the pathogenesis of influenzainfections. Treatment with anti-HMGB1 mAb provided partial protectionagainst pneumonia as well as encephalopathy in murine models ofinfluenza infections despite that the treatments did not affect viruspropagation in the lungs. (Nosaka N, et al., Anti-high mobility groupbox-1 monoclonal antibody treatment provides protection againstinfluenza A virus (H1N1)-induced pneumonia in mice, Critical Care(London, England), 2015; 19:249; Nosaka N, et al., Anti-high mobilitygroup box-1 monoclonal antibody treatment of brain edema induced byinfluenza infection and lipopolysaccharide, Journal of Medical Virology,2018; 90(7):1192-8; Hatayama K, et al., Combined effect ofanti-high-mobility group box-1 monoclonal antibody and peramivir againstinfluenza A virus-induced pneumonia in mice, Journal of MedicalVirology, 2019; 91(3):361-9). Combined anti-HMGB1 mAb and anti-viraltreatment offered almost complete protection. (Hatayama K, et al.,Combined effect of anti-high-mobility group box-1 monoclonal antibodyand peramivir against influenza A virus-induced pneumonia in mice,Journal of Medical Virology, 2019; 91(3):361-9). Improved survivalcombined with significantly attenuated histological changes andneutrophil infiltration in the lungs of influenza-inoculated mice wererecorded, despite that the treatment was based on xenogenic polyclonalantibodies against HMGB1. (Hou X Q, et al., Potential role ofhigh-mobility group box 1 protein in the pathogenesis of influenza H5N1virus infection, Acta virologica. 2014; 58(1):69-75). Therapy witheritoran, a TLR4 blocking compound ameliorated murine influenza-inducedlung injury by inhibiting the cytokine storm. Eritoran has been reportedto block HMGB1-mediated TLR4-dependent signaling in vitro, and toinhibit extracellular HMGB1 release in vivo by preventing necroptoticcell death in respiratory epithelial cells. (Shirey K A, et al., TheTLR4 antagonist Eritoran protects mice from lethal influenza infection,Nature, 2013; 497(7450):498-502; Shirey K A, et al., Novel strategiesfor targeting innate immune responses to influenza, Mucosal Immunology,2016; 9(5):1173-82).

Human respiratory syncytial virus (“HRSV”) is a leading cause of seriouslower respiratory tract infection (bronchiolitis and pneumonia) duringinfancy (Shi T, et al., Global, regional, and national disease burdenestimates of acute lower respiratory infections due to respiratorysyncytial virus in young children in 2015: a systematic review andmodelling study, Lancet (London, England), 2017; 390(10098):946-58) butcan also cause severe morbidity and mortality in the elderly and inimmunocompromised individuals. HRSV replicates in respiratory epithelialcells and promotes necroptosis and HMGB1 release. (Simpson J, et al.,RSV Infection Promotes Necroptosis and HMGB1 Release by AirwayEpithelial Cells, American Journal of Respiratory and Critical CareMedicine, 2020). High HMGB1 levels have been recorded in nasopharyngealsecretion from infected children. (Id.) Experimental RSV infectionsrespond well to therapies based on the HMGB1 antagonist glycyrrhizin(Manti S, et al., Induction of high-mobility group Box-1 in vitro and invivo by respiratory syncytial virus, Pediatr Res, 2018; 83(5):1049-5633)as well as to the synthetic TLR4 antagonist eritoran. (Rallabhandi P, etal., Respiratory syncytial virus fusion protein-induced toll-likereceptor 4 (TLR4) signaling is inhibited by the TLR4 antagonistsRhodobacter sphaeroides lipopolysaccharide and eritoran (E5564) andrequires direct interaction with MD-2, mBio, 2012; 3(4)).

In studies of patients with community-acquired bacterial pneumonia,HMGB1 levels were elevated in all patients and higher circulating HMGB1was associated with disease severity and mortality. (Angus D C, et al.,Circulating high-mobility group box 1 (HMGB1) concentrations areelevated in both uncomplicated pneumonia and pneumonia with severesepsis, Critical Care Medicine, 2007; 35(4):1061-7; Wang H L, et al.,Circulating level of high mobility group box1 predicts the severity ofcommunity acquired pneumonia: Regulation of inflammatory responses viathe cJun Nterminal signaling pathway in macrophages, Molecular MedicineReports, 2017; 16(3):2361-6). Patients with severe pneumonia and ARDSrequiring mechanical ventilation experience high rates of ICU mortality.Pseudomonas aeruginosa cause neutrophilic lung inflammation in cysticfibrosis patients, who express high HMGB1 levels in bronchoalveolarlavage fluid. Systemic treatment with anti-HMGB1 mAb in a preclinicalcystic fibrosis model conferred significant protection against P.aeruginosa-induced neutrophil recruitment, protein leak, and lunginjury. (Entezari M, et al., Inhibition of high-mobility group box 1protein (HMGB1) enhances bacterial clearance and protects againstPseudomonas Aeruginosa pneumonia in cystic fibrosis, Molecular Medicine(Cambridge, Mass.), 2012; 18:477-85). Treatment with partiallydesulfated heparin, a derivative with anti-inflammatory properties butminimal anti-coagulatory effects in two different models of pneumoniareduced airway HMGB1 levels and neutrophilic lung injury. (Griffin K L,et al., 2-O, 3-O-desulfated heparin inhibits neutrophil elastase-inducedHMGB-1 secretion and airway inflammation, American Journal ofRespiratory Cell and Molecular Biology, 2014; 50(4):684-9; Sharma L, etal., Partially-desulfated heparin improves survival in Pseudomonaspneumonia by enhancing bacterial clearance and ameliorating lung injury,Journal of immunotoxicology, 2014; 11(3):260-7).

Experimental work has unambiguously demonstrated a central mechanisticrole for HMGB1-mediated injury amplification and pulmonary inflammationin diverse conditions including trauma, shock, andischemia-reperfusion-injury. (Sodhi C P, et al., Intestinal EpithelialTLR-4 Activation Is Required for the Development of Acute Lung Injuryafter Trauma/Hemorrhagic Shock via the Release of HMGB1 from the Gut., JImmunol, 2015; 194(10):4931-9; Yang R, et al., Anti-HMGB1 neutralizingantibody ameliorates gut barrier dysfunction and improves survival afterhemorrhagic shock, Molecular Medicine (Cambridge, Mass.), 2006;12(4-6):105-14; Levy R M, et al., Systemic inflammation and remote organinjury following trauma require HMGB1, American Journal of PhysiologyRegulatory, Integrative and Comparative Physiology, 2007;293(4):R1538-44; Shimazaki J, et al., Systemic involvement ofhigh-mobility group box 1 protein and therapeutic effect ofanti-high-mobility group box 1 protein antibody in a rat model of crushinjury, Shock (Augusta, Ga.), 2012; 37(6):634-8; Okuma Y, et al.,Anti-high mobility group box-1 antibody therapy for traumatic braininjury, Annals of Neurology, 2012; 72(3):373-84; Kaczorowski D J, etal., Innate immune mechanisms in ischemia/reperfusion, Frontiers inBioscience (Elite edition), 2009; 1:91-8 (53-58)). A recentobservational study of trauma patients reported that a biphasic releaseof HMGB1, 3-6 h after injury, was a powerful predictor of outcome.(Ottestad W, et al., Biphasic Release of the Alarmin High Mobility GroupBox 1 Protein Early After Trauma Predicts Poor Clinical Outcome,Critical Care Medicine, 2019; 47(8):e614-e22). The second wave HMGB1plasma release was a consistent and highly accurate predictor of theduration of the subsequent need for ventilator support, reflectingsecondary remote lung injury. Interestingly, HMGB1 rendered robustpredictors like injury severity and physiological derangement (basedeficit) insignificant in multivariable models of outcome.

Sepsis

Severe sepsis (“sepsis”) is characterized by uncontrolled systemicinflammation in response to an infection or injury. Sepsis results inacute organ damage and ultimately failure; the mortality rate foruntreated sepsis often exceeds 60%. Although severe sepsis and thedanger it poses to patients has been recognized since the founding ofWestern medicine, its pathogenesis has remained obscure until the lasttwo decades, and it was only recognized by the CDC as a medicalemergency in August 2016. (Colby, S. and J. Ortman, Projections of theSize and Composition of the U.S. Population: 2014 to 2060, in CurrentPopulation Reports, 2014, U.S. Census Bureau: Washington, D.C.) Severesepsis (“sepsis” hereafter) is a syndrome in which an infectiousagent-bacteria or sometimes fungi-triggers runaway systemic inflammationleading to acute organ damage and ultimately failure. The initiatinginfection may be contracted through injury, but, for a majority of casesthe causative organism and the point of entry are never conclusivelydetermined. Without treatment, sepsis is frequently fatal. Vigilance,improved antimicrobial therapies, and advances in intensive care tosupport organ function have dramatically improved survival.Nevertheless, a bout of sepsis can have long-lasting physical andcognitive consequences for the patient, a fact that is becoming moreapparent as the number of survivors grows. (Angus, D. C., The lingeringconsequences of sepsis: a hidden public health disaster? JAMA, 2010,304(16): p. 1833-4; Iwashyna, T. J., et al., Long-term cognitiveimpairment and functional disability among survivors of sepsis, JAMA,2010, 304(16): p. 1787-94; Yende, S. and D. C. Angus, Long-term outcomesfrom sepsis, Curr Infect Dis Rep, 2007, 9(5): p. 382-6.)

Sepsis is the sixth-leading cause of hospitalization in the UnitedStates (CM, T. and A. R M, National Inpatient Hospital Costs: The MostExpensive Conditions by Payer, 2011., in HCUP Statistical Brief #160.2013, Agency for Healthcare Research and Quality: Rockville, Md.) and isthe most expensive condition treated due to the necessity of a stay inthe Intensive Care Unit (ICU) to resolve most cases. Rates of sepsis aresimilar in other economically advantaged countries; data for sepsisincidence is lacking in poorer countries and those without access tomodern medical care. It has been estimated that >19 million patientsworldwide develop sepsis annually, but this number likely substantiallyunderestimates the problem. (Adhikari, N. K., et al., Critical care andthe global burden of critical illness in adults, Lancet, 2010,376(9749): p. 1339-46; Fleischmann, C., et al., Assessment of GlobalIncidence and Mortality of Hospital-treated Sepsis Current Estimates andLimitations, Am J Respir Crit Care Med, 2016, 193(3): p. 259-72). In theUnited States, sepsis is the sixth most common reason forhospitalization and consumes 5.2% of total hospital costs, more than anyother disease or disorder (CM, T. and A. R M, National InpatientHospital Costs: The Most Expensive Conditions by Payer, 2011, in HCUPStatistical Brief #160, 2013, Agency for Healthcare Research andQuality: Rockville, Md.) These considerations prompted the CDC todeclare sepsis a medical emergency in 2016. (Control, C.f.D. CDCVitalSigns, 2016, cited Aug. 24, 2016, available from:www.cdc.gov/vitalsigns/sepsis/index.html). Given the lasting physicaland cognitive impairments to which survivors are prone and the lack ofany approved treatment, there is clearly a compelling need for acost-effective treatment for sepsis.

There is a high social cost to sepsis which resulted in more than 1.6million inpatient hospital stays in 2009 (Elixhauser, A., Septicemia inU.S. Hospital, 2009, in HCUP Statistical Brief #122. 2001, Agency forHealthcare Research and Quality: Rockville, Md.). Although mortalityfrom sepsis has declined in recent decades, it remains above 25% and wasthe leading cause of hospital death in 2009. (Id.; Angus, D. C., Sepsisand septic shock, N Engl J Med, 2013, 369(9): p. 840-51.). Patients withweakened immune systems are especially vulnerable. Indeed, more than onethird of hospitalizations for patients aged 65-84 years carried aprimary or secondary indication of sepsis (FIG. 2A).

The growing number of patients who survive the acute phase of sepsishave revealed that the danger associated with the disease extends longafter the initial hospital discharge. The long-term mortality aftersepsis is approximately 50% in the first year (Yende, S., Long-termoutcomes from sepsis, Curr Infect Dis Rep, 2007, 9(5): p. 382-6), risingto >81% over five years (Iwashyna, T. J., et al., Long-term cognitiveimpairment and functional disability among survivors of sepsis, JAMA,2010, 304(16): p. 1787-94). One common sequela of sepsis in survivors ispersistent anemia, which occurs in up to 60% of survivors and isassociated with poor outcome (Milbrandt, E. B., et al., Predicting lateanemia in critical illness, Crit Care, 2006, 10(1): p. R39; Nemeth, E.,Anemia of inflammation, Hematol Oncol Clin North Am, 2014, 28(4): p.671-81, vi.; Vincent, J. L., et al., Anemia and blood transfusion incritically ill patients, JAMA, 2002, 288(12): p. 1499-507). Sepsissurvivors are also more prone to exhibit diminished physical and/orcognitive function following their illness than age-matched controlshospitalized for non-sepsis indications (Iwashyna, T. J., et al.,Long-term cognitive impairment and functional disability among survivorsof sepsis, JAMA, 2010, 304(16): p. 1787-94). These persistentimpairments can lead to mood disorders and other sequelae that erodepatient quality of life and can strain caregivers (Angus, D. C., Thelingering consequences of sepsis: a hidden public health disaster? JAMA,2010, 304(16): p. 1833-4), causing Iwashyna and colleagues (2010) toconclude, “the burden of sepsis survivorship is a substantial,under-recognized public health problem with major implications forpatients, families, and the health care system.”

There is also a high economic cost associated with sepsis. In 2011, theaggregate cost for treating sepsis was $20.3 billion, consuming 5.2% ofthe cost for all hospitalizations and making it the most expensivecondition treated (CM, T. and A. R M, National Inpatient Hospital Costs:The Most Expensive Conditions by Payer, 2011., in HCUP Statistical Brief#160. 2013, Agency for Healthcare Research and Quality: Rockville, Md.;Elixhauser, A., B. Friedman, and E. Stranges, Septicemia in U.S.Hospital, 2009, in HCUP Statistical Brief #122. 2001, Agency forHealthcare Research and Quality: Rockville, Md.) (see FIG. 2B, showingthe costs of treating sepsis exceeded those of all other indications,again showing the prevalence and cost of sepsis). In the decadeterminating in 2008, the costs of treating sepsis ballooned at >11%annually. One driver of this growth is the increased incidence ofsepsis, a trend that is unlikely to abate as the US population greys(Colby, S. and J. Ortman, Projections of the Size and Composition of theU.S. Population: 2014 to 2060, in Current Population Reports, 2014, U.S.Census Bureau: Washington, D.C.) At the same time, the cost per stay fortreating sepsis has grown substantially (CM, T. and A. R M, NationalInpatient Hospital Costs: The Most Expensive Conditions by Payer, 2011.,in HCUP Statistical Brief #160. 2013, Agency for Healthcare Research andQuality: Rockville, Md.). With no approved therapy for sepsis and fewerthan one in three patients showing signs of active infection (Angus, D.C., Sepsis and septic shock, N Engl J Med, 2013, 369(9): p. 840-51),treatment focuses of monitoring and supporting organ function, typicallyin an Intensive Care Unit (ICU) or similar context.

The early clinical manifestations of sepsis include fever, elevatedheart rate, and increased respirations, which can make it difficult todistinguish from other common ailments like flu or a cold. As more organsystems become compromised, patients typically present withsignificantly decreased urine output (kidney dysfunction), delirium(impaired CNS function), labored breathing, and an erratic cardiacrhythm. These manifestations can vary greatly from patient to patient,depending on the site and cause of infection, the prior health of thepatient, and the time elapsed between infection and treatment. (Id.) Thefinal stage of the disease, septic shock, is marked by plummeting bloodpressure that is refractory to fluid support.

Although the first description of sepsis was likely recorded byHippocrates (Hippocrates, Hippocratic Writings, 1983: The PenguinGroup), the etiology of sepsis remained enigmatic until the recognitionthat dysregulation of the patient's own innate immune responseprecipitates the systemic inflammation that drives sepsis (Andersson,U., HMGB1 is a therapeutic target for sterile inflammation andinfection, Annu Rev Immunol, 2011, 29: p. 139-62; Angus, D. C., Sepsisand septic shock, N Engl J Med, 2013, 369(9): p. 840-51; Cerra, F. B.,The systemic septic response: multiple systems organ failure, Crit CareClin, 1985, 1(3): p. 591-607).

Elucidating the underlying molecular mechanisms has illuminated arelated paradox: sepsis-like symptoms that emerge after sterile injury(e.g., ischemia/reperfusion injury) stem from activating many of thesame pathways (Chen, G. Y., Sterile inflammation: sensing and reactingto damage, Nat Rev Immunol, 2010, 10(12): p. 826-37; Tsung, A., S.Tohme, High-mobility group box-1 in sterile inflammation, J Intern Med,2014, 276(5): p. 425-43). This mechanistic overlap poses the tantalizingpossibility that a single intervention could find clinical applicationin treating sepsis, autoimmune conditions, and other systemicinflammation syndromes.

Previous efforts to treat sepsis by controlling systemic inflammationhave all failed, most likely due to the unfavorable kinetics of theintended targets. For example, drugs intended to antagonize earlyeffectors of inflammation, such as TNFα (tumor necrosis factor), havesuch early and short therapeutic windows (within minutes to an hour ofinfection/injury) that they are unrealistic clinical candidates(Reinhart, K, Anti-tumor necrosis factor therapy in sepsis: update onclinical trials and lessons learned, Crit Care Med, 2001, 29(7 Suppl):p. S121-5). Indeed, targeting the early effectors of inflammation can beharmful; administering anti-TNFα actually worsens survival in a mousemodel of sepsis (Evans, G. F., et al., Differential expression ofinterleukin-1 and tumor necrosis factor in murine septic shock models,Circ Shock, 1989, 29(4): p. 279-90; Eskandari, M. K., et al., Anti-tumornecrosis factor antibody therapy fails to prevent lethality after cecalligation and puncture or endotoxemia, J Immunol, 1992, 148(9): p.2724-30; Remick, D., et al., Blockade of tumor necrosis factor reduceslipopolysaccharide lethality, but not the lethality of cecal ligationand puncture, Shock, 1995, 4(2): p. 89-95). Acute shock and tissueinjury are mediated by TNF and other early effectors of inflammation.This result illustrates an important distinction between earlypro-inflammatory effectors, like TNFα, and HMGB1, a late mediator ofinflammation.

The dramatically slower kinetics of HMGB1 release enable HMGB1 to betargeted at clinically realistic time points in experimental models ofsepsis: administering HMGB1 antagonists up to 24 hours after onset stillprovides significant therapeutic benefits. This is a unique resultcompared to all other interventions directed against the range ofpro-inflammatory molecules implicated in sepsis.

Wang, H., et al. were the first to identify the pro-inflammatoryactivity of HMGB1 (Wang, H., et al., HMG-1 as a late mediator ofendotoxin lethality in mice, Science, 1999, 285(5425): p. 248-51) and todemonstrate the beneficial effects of inhibiting HMGB1 signaling inanimal models of sepsis (Yang, H., et al., Reversing established sepsiswith antagonists of endogenous high-mobility group box 1, Proc Natl AcadSci USA, 2004, 101(1): p. 296-301). Targeting HMGB1 offers theopportunity to develop agents that can be given to patients duringcrisis to reduce mortality and during recovery to mitigate lingeringsequelae. Further, developing HMGB1 therapeutics has the potential to beground-breaking for myriad other diseases, in contexts as diverse astreating rheumatoid arthritis (Schierbeck, H., et al., Monoclonalanti-HMGB1 (high mobility group box chromosomal protein 1) antibodyprotection in two experimental arthritis models, Mol Med, 2011,17(9-10): p. 1039-44), suppressing inflammation following organtransplantation³¹, or mitigating lung pathologies associated with viraland/or bacterial infection (Entezari, M., et al., Inhibition ofhigh-mobility group box 1 protein (HMGB1) enhances bacterial clearanceand protects against Pseudomonas Aeruginosa pneumonia in cysticfibrosis, Mol Med, 2012, 18: p. 477-85; Nosaka, N., et al., Anti-highmobility group box-1 monoclonal antibody treatment provides protectionagainst influenza A virus (H1N1)-induced pneumonia in mice, Crit Care,2015, 19: p. 249).

Despite its long clinical history, the pathogenesis of sepsis had beenpoorly understood until the last two decades, when the molecularidentity of the primary late mediator of inflammation, HMGB1, wasdiscovered. (Wang, H., et al., HMG-1 as a late mediator of endotoxinlethality in mice, Science, 1999, 285(5425): p. 248-51). HMGB1 isreleased passively by damaged and necrotic cells to recruit leukocytesto the site of infection or injury; in turn, these innate immune cellsactively release HMGB1 to amplify the inflammatory response to fightactive infection or promote wound healing. (Andersson, U. and K. J.Tracey, HMGB1 is a therapeutic target for sterile inflammation andinfection, Annu Rev Immunol, 2011, 29: p. 139-62; Bertheloot, D. and E.Latz, HMGB1, IL-1alpha, IL-33 and S100 proteins: dual-function alarmins,Cell Mol Immunol, 2016). It is the dysregulation of HMGB1 signaling thatleads to sepsis.

HMGB1 antagonists have shown considerable promise in rodent models ofsepsis for promoting survival and mitigating long-term sequelae, evenwhen provided days after the onset of sepsis. Mice injected with amonoclonal antibody (mAb), 2G7 that binds and neutralizes HMGB1 hadsignificantly lower mortality than untreated mice or those injected withcontrol IgG that does not recognize HMGB1. (Qin, S., et al., Role ofHMGB1 in apoptosis-mediated sepsis lethality, J Exp Med, 2006, 203(7):p. 1637-42); See also, U.S. Pat. No. 8,138,141, incorporated herein byreference). In addition, mice who received mAb 2G7 treatment startingmore than a week after the onset of sepsis showed marked improvement ofsepsis-associated persistent anemia. (Valdes-Ferrer, S. I., et al.,HMGB1 mediates anemia of inflammation in murine sepsis survivors, MolMed, 2015). Hence, the therapeutic window for mAb 2G7 is unique andconveniently wide compared to other interventions that selectivelytarget pro-inflammatory cytokines. Another strategy to interrupt HMGB1signaling is to interfere with HMGB1 binding to its receptors. HMGB1 cantrigger the release of pro-inflammatory cytokines through the TLR4receptor.

Despite its prevalence, there is no approved treatment for sepsis. Thesole pharmacological intervention to receive FDA approval, activatedprotein C, was pulled from the market following concerns over safety andlack of efficacy (Bernard, G. R., et al., Efficacy and safety ofrecombinant human activated protein C for sepsis, N Engl J Med, 2001,344(10): p. 699-709). Systemic inflammation in sepsis likely is drivenby the alarmin protein High Mobility Group Box-1 protein (HMGB1). Levelsof circulating HMGB1 increase with sepsis severity (Wang, H., et al.,HMG-1 as a late mediator of endotoxin lethality in mice, Science, 1999,285(5425): p. 248-51; Gibot, S., et al., High-mobility group box 1protein plasma concentrations during septic shock, Intensive Care Med,2007, 33(8): p. 1347-53; Sunden-Cullberg, J., et al., Persistentelevation of high mobility group box-1 protein (HMGB1) in patients withsepsis and septic shock, Crit Care Med, 2005, 33(3): p. 564-73), whilethe appearance of anti-HMGB1 autoantibodies correlates with improvedoutcomes (Barnay-Verdier, S., et al., Emergence of autoantibodies toHMGB1 is associated with survival in patients with septic shock,Intensive Care Med, 2011, 37(6): p. 957-62) Likewise, injecting HMGB1antagonists rescues survival and other symptoms in a dose-dependentmanner (Qin, S., et al., Role of HMGB1 in apoptosis-mediated sepsislethality, J Exp Med, 2006, 203(7): p. 1637-42; Valdes-Ferrer, S. I., etal., HMGB1 mediates anemia of inflammation in murine sepsis survivors,Mol Med, 2015; Yang, H., et al., MD-2 is required for disulfideHMGB1-dependent TLR4 signaling, J Exp Med, 2015, 212(1): p. 5-14; Yang,H., et al., Reversing established sepsis with antagonists of endogenoushigh-mobility group box 1, Proc Natl Acad Sci USA, 2004, 101(1): p.296-301).

Severe Acute Respiratory Syndrome (SARS)

Coronaviruses (Order Nidovirales, family Coronaviridae, GenusCoronavirus) are enveloped positive-stranded RNA viruses that bud fromthe endoplasmic reticulum-Golgi intermediate compartment or thecis-Golgi network. Coronaviruses infect humans and animals and it isthought that there could be a coronavirus that infects every animal. Twohuman coronaviruses, 229E and OC43, are known to be the major causes ofthe common cold and can occasionally cause pneumonia in older adults,neonates, or immunocompromised patients. Human coronaviruses belongingto the Order Nidovirales specifically to the family Coronaviridae, werefirst identified in the mid-1960s. Six coronaviruses that have beenpreviously known to infect humans are: alpha coronaviruses 229E andNL63, and beta coronaviruses OC43, HKU1, SARS-CoV (the coronavirus thatcauses severe acute respiratory syndrome, or SARS), and MERS-CoV (thecoronavirus that causes Middle East Respiratory Syndrome, or MERS).

Severe acute respiratory syndrome (SARS) is caused by a newly identifiedvirus. SARS is a respiratory illness that has recently been reported inAsia, North America, and Europe. The causative agent of SARS wasidentified as a coronavirus. The World Health Organization reports thatthe cumulative number of reported probable cases of SARS from Nov. 1,2002 to Jul. 11, 2003 is 8,437 with 813 deaths, nearly a 10% death rate.Scientists currently believe that SARS will not be eradicated but willcause seasonal epidemics like the cold or influenza viruses.

A highly pathogenic coronavirus named SARS□CoV□2 (previously known as2019□nCoV) emerged in December 2019 in Wuhan, China, and is rapidlyspreading around the world. The virus has high sequence homology withSARS□CoV, with clinical symptoms similar to those reported for SARS□CoVand MERS□CoV. The most characteristic symptom of patients with SARS□CoVis respiratory distress which is often acute and the primary cause ofdeath. SARS□CoV was first identified in the Hubei province of China inDecember 2019. As of Mar. 11, 2020, it was declared a pandemic by theWorld Health Organization (WHO), acknowledging that the virus willlikely spread to all countries on the globe. As of Mar. 19, 2020, thevirus had infected more than 218,800 people worldwide, according toJohns Hopkins University, which is tracking cases reported by the WorldHealth Organization and additional sources. This virus is spreadingrapidly across the globe, having more than doubled the number ofinfected humans in a two-week period prior to Mar. 19, 2020. In responseto the outbreak, countries such as Italy, France and the Philippineshave enacted policies similar to those seen in China, placing millionsunder full or partial lockdowns. World-wide, there are currently stricttravel restrictions affecting hundreds of millions of citizens. In somehard-hit cities, residents have been unable to leave their apartmentsfor more than a month, while transport between major population hubs hasbeen limited or halted altogether.

SARS□CoV 2 causes mild symptoms in most patients but may, for unresolvedreasons, generate acute respiratory distress syndrome in vulnerableindividuals and may cause pneumonia. SARS-CoV-2 primarily infectsrespiratory epithelial cells utilizing angiotensin-converting enzyme 2receptors to enter the cells. Certain patients will go on to developacute lung injury progressing to severe acute respiratory distresssyndrome (ARDS) with sometimes lethal outcome. (Rothan H A, Byrareddy SN, The epidemiology and pathogenesis of coronavirus disease (COVID-19)outbreak, Journal of autoimmunity, 2020:102433; Lake M A, What we knowso far: COVID-19 current clinical knowledge and research, Clinicalmedicine (London, England), 2020; Huang C, et al., Clinical features ofpatients infected with 2019 novel coronavirus in Wuhan, China, Lancet(London, England), 2020; 395(10223):497-506; Guan W J, et al., ClinicalCharacteristics of Coronavirus Disease 2019 in China, The New EnglandJournal of Medicine, 2020). There is presently no approved treatmenttargeting molecules driving the inflammatory process. In the absence ofan approved anti-viral treatment or vaccination, there is an urgent needto identify key pathogenic molecules in bacterial and viral respiratoryinfections such as influenza, and in particular SARS□CoV□2, attainableto target with existing therapeutic compounds.

Acute Lung Injury

Acute lung injury (ALI) is a syndrome in which dysregulated immunesignaling causes pathologic inflammation of the lungs that damages thepulmonary epithelium and vasculature, leading to acute respiratoryinsufficiency and, frequently, death, with this syndrome being marked byrespiratory insufficiency, bilateral immune cell infiltrates and edema,and acute hypoxemia. (Rubenfeld G D, Incidence and outcomes of acutelung injury, N Engl J Med. 2005; 353(16):1685-93). ALI can be triggeredby insults ranging from infection, gastric acid aspiration, smokeinhalation, or sepsis. (Imai Y, Identification of oxidative stress andToll-like receptor 4 signaling as a key pathway of acute lung injury,Cell. 2008; 133(2):235-49; Johnson E R, Acute lung injury: epidemiology,pathogenesis, and treatment, J Aerosol Med Pulm Drug Deliv. 2010;23(4):243-52; Vande Vusse L K, The Epidemiology of Transfusion-relatedAcute Lung Injury Varies According to the Applied Definition of LungInjury Onset Time, Ann Am Thorac Soc. 2015; 12(9):1328-35). ALI resultsfrom runaway immune signaling: infected/injured epithelial cells releasepro-inflammatory signals that attract innate immune cells to the lungs,and these infiltrating macrophages and neutrophils compound epithelialdamage while releasing additional pro-inflammatory and/or cytotoxicsignals. Unchecked, this feedback loop establishes and reinforces adamaging cycle that compromises the junction between the lung epitheliumand alveolar-capillary membrane, leading to impaired gas exchange andedema. (Johnson E R, Acute lung injury: epidemiology, pathogenesis, andtreatment, J Aerosol Med Pulm Drug Deliv. 2010; 23(4):243-52). If thepathology progresses sufficiently, it can culminate in respiratoryfailure and death. (Imai Y, Identification of oxidative stress andToll-like receptor 4 signaling as a key pathway of acute lung injury,Cell, 2008; 133(2):235-49; Johnson E R, Matthay M A, Acute lung injury:epidemiology, pathogenesis, and treatment, Johnson E R, Acute lunginjury: epidemiology, pathogenesis, and treatment, J Aerosol Med PulmDrug Deliv., 2010; 23(4):243-52; Rubenfeld G D, Incidence and outcomesof acute lung injury, N Engl J Med. 2005; 353(16):1685-93). FIG. 3 is agraphical representation of ALI incidence and mortality across agecohorts, subdivided by predisposing factors.

ALI has been described in the medical literature since 1967 (Ashbaugh DG, Acute respiratory distress in adults, Lancet, 1967; 2(7511):319-23),yet there remains no effective pharmacotherapy. (Cepkova M,Pharmacotherapy of acute lung injury and the acute respiratory distresssyndrome, J Intensive Care Med, 2006; 21(3):119-43; Raghavendran K,Pharmacotherapy of acute lung injury and acute respiratory distresssyndrome, Curr Med Chem., 2008; 15(19):1911-24).

Acute Lung Injury is an inflammatory disorder. When cells of thealveolar epithelium become damaged through injury or infection, theyrelease pro-inflammatory signals to recruit macrophages and neutrophilsinto the alveolar space. These innate immune cells phagocytose necroticand apoptotic cells and assist with controlling the pathogen load, alongwith releasing cytotoxic and pro-inflammatory cytokines and HMGB1.(Johnson E R, Acute lung injury: epidemiology, pathogenesis, andtreatment, J Aerosol Med Pulm Drug Deliv., 2010; 23(4):243-52;Damjanovic D, Immunopathology in influenza virus infection: uncouplingthe friend from foe, Clin Immunol., 2012; 144(1):57-69; Lin K L, CCR2+monocyte-derived dendritic cells and exudate macrophages produceinfluenza-induced pulmonary immune pathology and mortality, J Immunol.,2008; 180(4):2562-72). This positive feedback loop becomes dysregulatedduring ALI, with pathological and often fatal results. FIGS. 4A and 4Bshow how dysregulated inflammation causes ALI with FIG. 4A showing thefeedback loop that drives immunopathology in ALI and FIG. 4B showing howHMGB1 levels roughly correlate with tissue damage and negative outcomes.FIG. 4 B is adapted from Andersson U, HMGB1 is a therapeutic target forsterile inflammation and infection, Annu Rev Immunol., 2011; 29:139-62.

Hallmarks of ALI include excessive neutrophil infiltration leading todamage to healthy epithelium adjacent to the original injury site(Johnson E R, Acute lung injury: epidemiology, pathogenesis, andtreatment, J Aerosol Med Pulm Drug Deliv., 2010; 23(4):243-52;Taubenberger J K, Morens D M, The pathology of influenza virusinfections, Annu Rev Pathol., 2008; 3:499-522.27), loss of epithelialmembrane integrity and accumulation of proteinaceous fluid in the lungs(Johnson E R, Acute lung injury: epidemiology, pathogenesis, andtreatment, J Aerosol Med Pulm Drug Deliv., 2010; 23(4):243-52), andabnormally high levels of cytokines and chemokines in the serum andlungs. The severity of this cytokine storm often correlates with fataloutcomes. (Johnson E R, J Aerosol Med Pulm Drug Deliv., 2010;23(4):243-52; Damjanovic D, Immunopathology in influenza virusinfection: uncoupling the friend from foe, Clin Immunol. 2012;144(1):57-69; Lin K L, CCR2+ monocyte-derived dendritic cells andexudate macrophages produce influenza-induced pulmonary immune pathologyand mortality, J Immunol., 2008; 180(4):2562-72. PubMed PMID: 18250467;Taubenberger J K, Fatal outcome of human influenza A (H5N1) isassociated with high viral load and hypercytokinemia, Nat Med., 2006;12(10):1203-7; The pathology of influenza virus infections, Annu RevPathol., 2008; 3:499-522; de Jong M D, Fatal outcome of human influenzaA (H5N1) is associated with high viral load and hypercytokinemia, NatMed., 2006; 12(10):1203-7).

Acute respiratory infection caused by influenza is one of the mostcommon causes of ALI. Although seasonal and pandemic flu strains differin virulence, they share a common pathology in that ALI is a hallmark ofcases of severe illness. Other risk factors that lead to dysregulatedinflammatory signaling in the lung can trigger ALI. These includesepsis, non-influenza pulmonary infections, smoke or toxic gasinhalation, gastric acid aspiration, and transfusion reactions, amongothers. (Imai Y, Identification of oxidative stress and Toll-likereceptor 4 signaling as a key pathway of acute lung injury, Cell, 2008;133(2):235-49; Johnson E R, Acute lung injury: epidemiology,pathogenesis, and treatment, J Aerosol Med Pulm Drug Deliv., 2010;23(4):243-52; Vande Vusse L K, The Epidemiology of Transfusion-relatedAcute Lung Injury Varies According to the Applied Definition of LungInjury Onset Time, Ann Am Thorac Soc., 2015; 12(9):1328-35). Mechanicalventilation and other treatments for ALI also can cause additionalairway injury that exacerbates the condition. (Parsons P E, NetworkNARDSCT. Lower tidal volume ventilation and plasma cytokine markers ofinflammation inpatients with acute lung injury, Crit Care Med. 2005;33(1):1-6; discussion 230-2; Ranieri V M, Effect of mechanicalventilation on inflammatory mediators in patients with acute respiratorydistress syndrome: a randomized controlled trial, JAMA, 1999;282(1):54-61).

The incidence of ALI in the United States has been estimated atapproximately 200,000 cases annually. (Martin T R, A TRIFfic perspectiveon acute lung injury, Cell, 2008; 133(2):208-10; Rubenfeld G D,Incidence and outcomes of acute lung injury, N Engl J Med. 2005;353(16):1685-93) Extrapolating this rate to the world population (likelyan underestimation) suggests that there are more than 4.5 million ALIcases globally each year. The prevalence and severity of ALI increaseswith age and the presence of predisposing clinical factors (see FIGS. 4Aand 4B adapted from Rubenfeld G D, Incidence and outcomes of acute lunginjury, N Engl J Med., 2005; 353(16):1685-93), with the mortality riskvarying from 29% to over 40% for the elderly. (Johnson E R, Acute lunginjury: epidemiology, pathogenesis, and treatment, J Aerosol Med PulmDrug Deliv., 2010; 23(4):243-52). Patients who survive ALI face diverseand lasting challenges from cognitive and motor deficits to psychiatricand mood disorders. (Rubenfeld G D, Incidence and outcomes of acute lunginjury, N Engl J Med. 2005; 353(16):1685-93); Herridge M S, CanadianCritical Care Trials G. One-year outcomes in survivors of the acuterespiratory distress syndrome, N Engl J Med, 2003; 348(8):683-93; RuhlAP, Health care resource use and costs of two-year survivors of acutelung injury. An observational cohort study, Ann Am Thorac Soc., 2015;12(3):392-401; Schelling G, Health-related quality of life andposttraumatic stress disorder in survivors of the acute respiratorydistress syndrome, Crit Care Med., 1998; 26(4):651-9). Indeed, it hasbeen estimated that ALI survivors consume more than $2 billion inhealthcare in the U.S. annually. (Ruhl A P, Health care resource use andcosts of two-year survivors of acute lung injury. An observationalcohort study, Ann Am Thorac Soc., 2015; 12(3):392-401), and thesenumbers likely will double as the graying U.S. population swells thenumber of people at high risk due to age. (Rubenfeld G D, Incidence andoutcomes of acute lung injury, N Engl J Med, 2005; 353(16):1685-93).Thus, there is a compelling need for a cost-effective treatment for ALI.

The social and economic costs of ALI are high, with approximately 75,000people succumbing to ALI in the U.S. each year (Rubenfeld G D, Incidenceand outcomes of acute lung injury, N Engl J Med., 2005;353(16):1685-93). The intensive support that ALI patients require tosurvive the acute phase consumes a staggering level of medicalresources. For example, it has been estimated that ALI is responsiblefor a combined 2.2 million ICU days for patients annually. Moreover, thecosts of ALI extend far beyond the initial ICU stay: approximatelytwo-thirds of survivors require extended rehabilitative care before theycan be discharged to home. Without a breakthrough treatment, thesenumbers could double in the next 25 years due to the explosion in theproportion of the US population who are at high-risk due to age.

Cognitive abnormalities, weakness, depression, and even post-traumaticstress disorder are common and lingering sequelae for which ALIsurvivors are treated that frequently require inpatient admission tohospitals of skilled nursing/rehabilitation facilities. (Rubenfeld G DIncidence and outcomes of acute lung injury, N Engl J Med., 2005;m353(16):1685-93; Herridge M S, Canadian Critical Care Trials G.One-year outcomes in survivors of the acute respiratory distresssyndrome, N Engl J Med., 2003; 348(8):683-93; Ruhl A P Health careresource use and costs of two-year survivors of acute lung injury. Anobservational cohort study, Ann Am Thorac Soc., 2015; 12(3):392-401;Schelling G, Health-related quality of life and posttraumatic stressdisorder in survivors of the acute respiratory distress syndrome, CritCare Med., 1998; 26(4):651-9). Indeed, one study that followed ALIsurvivors for two years after their initial discharge observed that 80%were readmitted at a median cost of $35,529 during the study period,primarily in the first year. (Ruhl A P, Health care resource use andcosts of two-year survivors of acute lung injury, An observationalcohort study, Ann Am Thorac Soc. 2015; 12 (3):392-401). Thus, aconservative estimate of the ongoing costs incurred to treat ALIsurvivors in the U.S. exceeds $2 billion annually.

Although ALI may be precipitated by diverse insults, recent evidencesuggests that the over-production of pro-inflammatory molecules thatultimately leads to pathology is mediated by the Toll-like Receptor TLR4and HMGB1, the primary late mediator of inflammation. (Imai Y,Identification of oxidative stress and Toll-like receptor 4 signaling asa key pathway of acute lung injury, Cell, 2008; 133(2):235-49; Nosaka N,Anti-high mobility group box-1 monoclonal antibody treatment providesprotection against influenza A virus (H1N1)-induced pneumonia in mice,Crit Care, 2015; 19:249; Shirey K A, Lai W, Novel strategies fortargeting innate immune responses to influenza, Mucosal Immunol., 2016;9(5):1173-82; Shirey K A, The TLR4 antagonist Eritoran protects micefrom lethal influenza infection, Nature, 2013; 497(7450):498-502).HMGB1, whose major signaling receptor is TLR4, is released passively byapoptotic and necrotic cells to recruit leukocytes to the site ofinfection or injury; in turn, these innate immune cells actively releaseHMGB1 to amplify the inflammatory response to fight active infection orpromote wound healing. A breakdown in the regulation of this feedbackloop can lead to uncontrolled inflammation. Mice deficient for TLR4 areless susceptible to ALI (Imai Y, Identification of oxidative stress andToll-like receptor 4 signaling as a key pathway of acute lung injury,Cell. 2008; 133(2):235-49; Martin T R, A TRIFfic perspective on acutelung injury, Cell, 2008; 133(2):208-10) and a TLR4 antagonist protectsagainst lethality in influenza-induced ALI. (Shirey K A, Novelstrategies for targeting innate immune responses to influenza. MucosalImmunol, 2016; 9(5):1173-82; Shirey K A, The TLR4 antagonist Eritoranprotects mice from lethal influenza infection, Nature, 2013;497(7450):498-502). Likewise, HMGB1 antagonists promote survival whenadministered following lethal influenza infection. Mice injected with amonoclonal antibody (mAb) that binds and neutralizes HMGB1 hadsignificantly lower mortality than those injected with control IgG thatdoes not recognize HMGB1. (Nosaka N, Anti-high mobility group box-1monoclonal antibody treatment provides protection against influenza Avirus (H1N1)-induced pneumonia in mice, Crit Care, 2015; 19:249: Seealso, U.S. Pat. No. 8,138,141, incorporated herein by reference).Another strategy to interrupt HMGB1 signaling is to interfere with HMGB1binding to the TLR4/MD-2 receptor complex.

Peripheral Neuropathy

Over 29 million people are diagnosed with diabetes in the U.S., andanother 86 million adults have prediabetes, with an estimated 15 to 30percent of people with prediabetes developing type 2 diabetes withinfive years. (Control CfD, Prevention, National diabetes statisticsreport: estimates of diabetes and its burden in the United States,Atlanta, Ga.: US Department of Health and Human Services, (2014)). Themost common complication of diabetes is diabetic peripheral neuropathy(DPN), a painful condition with a lifetime prevalence of 66%.(Charnogursky, G., Diabetic neuropathy, Handbook of clinical neurology,2014; 120: 773-785); Dyck P. J., The prevalence by staged severity ofvarious types of diabetic neuropathy, retinopathy, and nephropathy in apopulation-based cohort: the Rochester Diabetic Neuropathy Study,Neurology, 1993; 43(4): 817-824). The total annual cost of DPN and itscomplications in the U.S. was estimated to be between $4.6 and $13.7billion in 2001, and DPN accounts for up to 27% of direct medical costsof diabetes. (Gordois A, The health care costs of diabetic peripheralneuropathy in the US, Diabetes Care, June 2003; 26(6):1790-1795). Theonly treatments currently available for DPN are disease state modifierssuch as tight blood glucose control, and chronic pain medication. (BrilV., Treatments for diabetic neuropathy, Journal of the PeripheralNervous System, 2012; 17(s2):22-27; Javed S., Treatment of painfuldiabetic neuropathy, Therapeutic advances in chronic disease, 2015;6(1):15-28). However, even with intensive insulin therapy, approximately25% of patients still developed DPN (Control D, Group CTR, The effect ofintensive treatment of diabetes on the development and progression oflong-term complications in insulin-dependent diabetes mellitus, N. Engl.J. Med., 1993; (329): 977-986). As diabetic neuropathic pain respondspoorly to current standard pain treatments (Baron R., Neuropathic pain:diagnosis, pathophysiological mechanisms, and treatment, The LancetNeurology, 2010; 9(8): 807-819), novel mechanisms mediating thedevelopment of neuropathic pain have been proposed. (Dworkin R. H.,Advances in neuropathic pain: diagnosis, mechanisms, and treatmentrecommendations, Archives of neurology, 2003; 60(11): 1524-1534; DrayA., Neuropathic pain: emerging treatments, British Journal ofAnaesthesia. 2008; 101(1): 48-58); Ossipov M. H., Challenges in thedevelopment of novel treatment strategies for neuropathic pain, NeuroRx,2005; 2(4): 650-661; Costigan M., Neuropathic pain: a maladaptiveresponse of the nervous system to damage, Annual review of neuroscience,2009; 32: 1-32). Few of these mechanisms have been translated into aneffective mechanism-based therapy. (Dworkin R. H., Advances inneuropathic pain: diagnosis, mechanisms, and treatment recommendations,Archives of neurology, 2003; 60(11): 1524-1534; Ossipov M. H.,Challenges in the development of novel treatment strategies forneuropathic pain, NeuroRx, 2005; 2(4): 650-661).

As discussed above, HMGB1 is a late mediator of inflammation. Inanimals, all cells synthesize HMGB1; healthy cells sequester it in thenucleus, where it serves as a transcription factor. (Andersson U, HMGB1is a therapeutic target for sterile inflammation and infection, Annu RevImmunol., 2011; 29:139-62; Wang H, HMG-1 as a late mediator of endotoxinlethality in mice, Science, 1999; 285(5425):248-51). Cellular damage,necrosis, and apoptosis result in the passive release of HMGB1 into theextracellular space, which can recruit leukocytes to the site of aninjury or infection. In turn, these monocytes, tissue macrophages, andother cells of the innate immune system actively secrete HMGB1 whenactivated by pathogen-derived stimuli, exosomes, or pro-inflammatorycytokines. Depending upon its oxidation state and which of its receptorsare engaged, extracellular HMGB1 can trigger a variety of outcomes(reviewed in Lotze M T, High-mobility group box 1 protein (HMGB1):nuclear weapon in the immune arsenal Nat Rev Immunol., 2005;5(4):331-42; Yang H, Targeting HMGB1 in inflammation, Biochim BiophysActa., 2010; 1799(1-2):149-56 and Harris H E, HMGB1: a multifunctionalalarmin driving autoimmune and inflammatory disease, Nat Rev Rheumatol.,2012; 8(4):195-202), including secretion of additional HMGB1 to sustainthe immune response until the insult is resolved. These characteristics,pro-inflammatory cytokine activity and prolonged release, recommendHMGB1 as an attractive therapeutic target in inflammatory diseases.(Andersson U, HMGB1 is a therapeutic target for sterile inflammation andinfection, Annu Rev Immunol, 2011; 29:139-62).

HMGB1 is now well known as a critical mediator in inflammation, withanimal studies demonstrating that HMGB1 is a key mediator ofinflammation, interacting with as many as 15 distinct receptor systems(Maeda T., HMGB1 as a potential therapeutic target for neuropathic pain,Journal of Pharmacological Sciences., 2013; 123(4): 301-305; Wan W., Theemerging role of HMGB1 in neuropathic pain: a potential therapeutictarget for neuroinflammation, Journal of Immunology Research, (2016);Andersson U., HMGB1 is a therapeutic target for sterile inflammation andinfection, Annual Review of Immunology, 2011; 29:139-162; Yang H., Themany faces of HMGB1: molecular structure-functional activity ininflammation, apoptosis, and chemotaxis, Journal of Leukocyte Biology,2013; 93(6): 865-873); and causing organ damage and epithelial barrierfailure in trauma, sepsis, shock and ischemia/reperfusion injury. (WanW., The emerging role of HMGB1 in neuropathic pain: a potentialtherapeutic target for neuroinflammation, Journal of ImmunologyResearch, (2016); Andersson U., HMGB1 is a therapeutic target forsterile inflammation and infection, Annual Review of Immunology, 2011;29: 139-162; Magna M, The role of HMGB1 in the pathogenesis ofinflammatory and autoimmune diseases, Molecular Medicine, 2014;20(1):138; Peter K., HMGB1 signals danger in acute coronary syndrome:emergence of a new risk marker for cardiovascular death?Atherosclerosis, 2012; 221(2): 317-318; Liu Y., HMGB1: roles in baseexcision repair and related function, Biochimica et Biophysica Acta(BBA)-Gene Regulatory Mechanisms, 2010; 1799(1): 119-130). While HMGB1is a well-established mediator in inflammatory diseases, only recentlyhave investigators begun to address the role of HMGB1 in pain. Recentwork has shown that HMGB1 plays a vital role in the pathophysiologicalmechanisms of pain, including cancer, arthritis, pancreatitis-inducedpain, headache, and peripheral nerve injury induced neuropathic pain.(Nishida T., Involvement of high mobility group box 1 in the developmentand maintenance of chemotherapy-induced peripheral neuropathy in rats,Toxicology, 2016; 365: 48-58; Feldman P., The persistent release ofHMGB1 contributes to tactile hyperalgesia in a rodent model ofneuropathic pain, Journal of Neuroinflammation, 2012; 9(1): 180; AlletteY. M., Identification of a functional interaction of HMGB1 with Receptorfor Advanced Glycation End-products in a model of neuropathic pain,Brain, Behavior, and Immunity. 2014; 42:169-177; Kuang X., Effects ofintrathecal epigallocatechin gallate, an inhibitor of Toll-like receptor4, on chronic neuropathic pain in rats, European Journal ofPharmacology, 2012; 676(1): 51-56; Nakamura Y., Neuropathic pain in ratswith a partial sciatic nerve ligation is alleviated by intravenousinjection of monoclonal antibody to high mobility group box-1, PloS One,2013; 8(8): e73640; Shibasaki M., Induction of high mobility group box-1in dorsal root ganglion contributes to pain hypersensitivity afterperipheral nerve injury, Pain, 2010; 149(3): 514-521; Grace P. M.,Pathological pain and the neuroimmune interface, Nature ReviewsImmunology, 2014; 14(4): 217-231; Tong W., Spinal high-mobility groupbox 1 contributes to mechanical allodynia in a rat model of bone cancerpain, Biochemical and Biophysical Research Communications, 2010; 395(4):572-576; Agalave N. M., Spinal HMGB1 induces TLR4-mediated long-lastinghypersensitivity and glial activation and regulates pain-like behaviorin experimental arthritis, PAIN®, 2014; 155(9): 1802-1813; Ma Y-Q,Tanshinone IIA downregulates HMGB1 and TLR4 expression in a spinal nerveligation model of neuropathic pain, Evidence-Based Complementary andAlternative Medicine, (2014); Maeda T., HMGB1 as a potential therapeutictarget for neuropathic pain, Journal of pharmacological sciences., 2013;123(4): 301-305; Chacur M., A new model of sciatic inflammatory neuritis(SIN): induction of unilateral and bilateral mechanical allodyniafollowing acute unilateral peri-sciatic immune activation in rats, Pain,2001; 94(3): 231-244; Tanaka J., Recombinant human solublethrombomodulin prevents peripheral HMGB1-dependent hyperalgesia in rats,British Journal of Pharmacology, 2013; 170(6): 1233-1241; Karatas H.,Spreading depression triggers headache by activating neuronal Panx1channels, Science, 2013; 339(6123): 1092-1095; Das N., HMGB1 activatesproinflammatory signaling via TLR5 leading to allodynia, Cell Reports,2016; 17(4): 1128-1140). Persistent inflammation in response toexcessively released HMGB1 contributes to the sequelae of inflammatorypain. Because of the similarities of inflammatory response in thedevelopment of diabetes, the role of HMGB1 and HMGB1-mediatedinflammatory pathways in adipose tissue inflammation, insulinresistance, and islet dysfunction in diabetes, as well as painful DPN,have also been reported. (Zhao X., Inhibition of CaMKIV relievesstreptozotocin-induced diabetic neuropathic pain through regulation ofHMGB1, BMC Anesthesiology, 2016; 16(1): 27; Ren P-C, High-mobility groupbox 1 contributes to mechanical allodynia and spinal astrocyticactivation in a mouse model of type 2 diabetes, Brain Research Bulletin,2012; 88(4): 332-337; Abu El-Asrar A M, The proinflammatory cytokinehigh-mobility group box-1 mediates retinal neuropathy induced bydiabetes, Mediators of Inflammation, (2014); Tsao C., Expression ofhigh-mobility group box protein 1 in diabetic foot atherogenesis,Genetics and Molecular Research, 2015; 14(2): 4521-4531; Zhao H., HMGB-1as a potential target for the treatment of diabetic retinopathy, MedicalScience Monitor: International Medical Journal Of Experimental AndClinical Research, 2015; 21: 3062). Given that HMGB1-TLR4/MD-2 signalingpathway plays a pivotal role in inflammation, HMGB1 and its downstreamreceptor TLR4 may serve as potential antidiabetic targets.

Growing evidence supports that high-mobility group box 1 protein (HMGB1)plays a vital role in the pathophysiological mechanisms of neuropathicpain (NP). (Nishida T., Involvement of high mobility group box 1 in thedevelopment and maintenance of chemotherapy-induced peripheralneuropathy in rats, Toxicology, 2016; 365: 48-58; Feldman P., Thepersistent release of HMGB1 contributes to tactile hyperalgesia in arodent model of neuropathic pain, Journal of neuroinflammation, 2012;9(1): 180; Allette Y. M., Identification of a functional interaction ofHMGB1 with Receptor for Advanced Glycation End-products in a model ofneuropathic pain, Brain, Behavior, And Immunity, 2014; 42:169-177; KuangX., Effects of intrathecal epigallocatechin gallate, an inhibitor ofToll-like receptor 4, on chronic neuropathic pain in rats, EuropeanJournal Of Pharmacology, 2012; 676(1): 51-56; Nakamura Y., Neuropathicpain in rats with a partial sciatic nerve ligation is alleviated byintravenous injection of monoclonal antibody to high mobility groupbox-1, Plos One, 2013; 8(8): e73640; Shibasaki M., Induction of highmobility group box-1 in dorsal root ganglion contributes to painhypersensitivity after peripheral nerve injury, Pain, 2010; 149(3):514-521; Grace P. M., Pathological pain and the neuroimmune interface,Nature Reviews Immunology, 2014; 14(4): 217-231; Tong W., Spinalhigh-mobility group box 1 contributes to mechanical allodynia in a ratmodel of bone cancer pain, Biochemical And Biophysical ResearchCommunications, 2010; 395(4): 572-576; Agalave N. M., Spinal HMGB1induces TLR4-mediated long-lasting hypersensitivity and glial activationand regulates pain-like behavior in experimental arthritis, PAIN®, 2014;155(9): 1802-1813; Ma Y-Q, Tanshinone IIA downregulates HMGB1 and TLR4expression in a spinal nerve ligation model of neuropathic pain,Evidence-Based Complementary and Alternative Medicine, (2014); Maeda T.,HMGB1 as a potential therapeutic target for neuropathic pain, Journal OfPharmacological Sciences, 2013; 123(4): 301-305; Chacur M., A new modelof sciatic inflammatory neuritis (SIN): induction of unilateral andbilateral mechanical allodynia following acute unilateral peri-sciaticimmune activation in rats, Pain, 2001; 94(3): 231-244; Tanaka J.,Recombinant human soluble thrombomodulin prevents peripheralHMGB1-dependent hyperalgesia in rats, British Journal Of Pharmacology,2013; 170(6): 1233-1241; Karatas H., Spreading depression triggersheadache by activating neuronal Panx1 channels, Science, 2013;339(6123): 1092-1095) (Das N., HMGB1 activates proinflammatory signalingvia TLR5 leading to allodynia, Cell Reports, 2016; 17(4): 1128-1140).This includes evidence that HMGB1 plays a vital role in thepathophysiological mechanisms for diabetic neuropathic pain. (Zhao X.,Inhibition of CaMKIV relieves streptozotocin-induced diabeticneuropathic pain through regulation of HMGB1, BMC Anesthesiology, 2016;16(1): 27; Ren P-C, High-mobility group box 1 contributes to mechanicalallodynia and spinal astrocytic activation in a mouse model of type 2diabetes, Brain Research Bulletin, 2012; 88(4): 332-337). Numerousreports and studies have shown that HMGB1 is an essential inflammatorypronociceptive factor that interacts with many other mediators. (AgalaveN. M., Spinal HMGB1 induces TLR4-mediated long-lasting hypersensitivityand glial activation and regulates pain-like behavior in experimentalarthritis, PAIN®, 2014; 155(9): 1802-1813; Maeda T., HMGB1 as apotential therapeutic target for neuropathic pain, Journal ofPharmacological Sciences, 2013; 123(4): 301-305) (Wan W., The emergingrole of HMGB1 in neuropathic pain: a potential therapeutic target forneuroinflammation, Journal of Immunology Research, (2016); Yang H., HighMobility Group Box Protein 1 (HMGB1): The Prototypical Endogenous DangerMolecule, Molecular Medicine (Cambridge, Mass.), 2015; 21 Suppl 1:S6-S12). Lower levels of HMGB1 are bactericidal, stimulate neuritegrowth and enhance motility of smooth muscle cells and fibroblasts.Higher levels of HMGB1 are pathological; activate macrophages to releasecytokines including TNF, IL-1α, IL-1β, IL-6, MIP1α, and IL-8 (see FIG. 5which shows the biological effects of HMGB1). (Andersson U, Tracey K J,HMGB1 is a therapeutic target for sterile inflammation and infection,Annual Review of Immunology, 2011; 29: 139-162). These HMGB1-mediatedinflammatory pathways underlie adipose tissue inflammation, insulinresistance, and islet dysfunction in diabetes, as well as development ofpainful DPN. (Zhao X., Inhibition of CaMKIV relievesstreptozotocin-induced diabetic neuropathic pain through regulation ofHMGB1, BMC Anesthesiology, 2016; 16(1): 27; Abu El-Asrar A M, Theproinflammatory cytokine high-mobility group box-1 mediates retinalneuropathy induced by diabetes, Mediators of Inflammation, (2014); TsaoC., Expression of high-mobility group box protein 1 in diabetic footatherogenesis, Genetics and Molecular Research, 2015; 14(2): 4521-4531;Zhao H., HMGB-1 as a potential target for the treatment of diabeticretinopathy, Medical Science Monitor: International Medical Journal ofExperimental and Clinical Research, 2015; 21: 3062). Thus,HMGB1-blocking approach is beneficial to diabetic patients in general.

While inhibition of HMGB1 using neutralizing monoclonal antibody reducesneuropathic pain in multiple animal models, the challenge to thedevelopment of a safe and effective HMGB1-based treatment for painfulDPN is the diverse molecular localizations and functions of HMGB1isoforms. (Yang H., Redox modification of cysteine residues regulatesthe cytokine activity of high mobility group box-1 (HMGB1), MolecularMedicine, 2012; 18(1): 250; Magna M, Pisetsky D S., The role of HMGB1 inthe pathogenesis of inflammatory and autoimmune diseases, MolecularMedicine. 2014; 20(1):138; Peter K., HMGB1 signals danger in acutecoronary syndrome: emergence of a new risk marker for cardiovasculardeath?, Atherosclerosis, 2012; 221(2): 317-318; Zhu L., High-mobilitygroup box 1 induces neuron autophagy in a rat spinal root avulsionmodel, Neuroscience, 2016; 315: 286-295; Liu Y., HMGB1: roles in baseexcision repair and related function, Biochimica et Biophysica Acta(BBA)-Gene Regulatory Mechanisms, 2010; 1799(1): 119-130; Lian Y-J,Ds-HMGB1 and fr-HMGB induce depressive behavior throughneuroinflammation in contrast to nonoxid-HMGB1, Brain, Behavior, andImmunity, 2017; 59: 322-332). It is known that there are three isoformsof HMGB1, and distinct immune functions via separate receptor systemshave been attributed to each (See FIGS. 6A-6C which show the three knownisoforms of HMGB1). HMGB1 contains 3 cysteines (Cys) at positions 23, 45and 106. Evidence has accumulated that the redox status of thesecysteines influences the corresponding extracellular chemokine orcytokine-inducing properties. Specifically, evidence suggests that HMGB1with all cysteine residues reduced (fully reduced HMGB1) binds to CXCL12and stimulates immune cell infiltration via the CXCR4 receptor.Similarly, partially oxidized HMGB1, with a Cys23-Cys45 disulfide bondand a reduced Cys106 (disulfide HMGB1), has been shown to activateimmune cells via the TLR4/MD-2 receptor. Evidence suggests that allcysteines oxidized (sulfonyl HMGB1) is devoid of immune activity. (YangH., Redox modification of cysteine residues regulates the cytokineactivity of high mobility group box-1 (HMGB1), Molecular Medicine, 2012;18(1): 250) (Yang H., MD-2 is required for disulfide HMGB1-dependentTLR4 signaling, Journal of Experimental Medicine, 2015: jem. 20141318;Antoine D. J., A systematic nomenclature for the redox states of highmobility group box (HMGB) proteins, Molecular medicine, 2014; 20(1):135; Venereau E., Mutually exclusive redox forms of HMGB1 promote cellrecruitment or proinflammatory cytokine release, Journal of ExperimentalMedicine, 2012; 209(9): 1519-1528; Kim S., Signaling of high mobilitygroup box 1 (HMGB1) through toll-like receptor 4 in macrophages requiresCD14, Molecular Medicine, 2013; 19(1): 88).

While there is an array of established HMGB1 inhibitors, many of themlack specificity which may dampen their significance for furtherdevelopment. (Andersson U., HMGB1 is a therapeutic target for sterileinflammation and infection, Annual Review of Immunology, 2011; 29:139-162).

Pharmacological Compounds that Inhibit HMGB1

FIG. 7 shows the inhibition of HMGB1-RAGE-TLR4-mediated inflammation byapproved pharmacological compounds. The formation of proinflammatoryHMGB1-partner molecule complexes is counteracted by thrombomodulin,heparin, haptoglobin, and glycyrrhizin. RAGE-HMGB1-mediated activitiesare inhibited by acetylcholine, heparin, statins, dexmedetomidine, andketamine. TLR4-HMGB1 mediated activation is downregulated byacetylcholine, heparin, statins, resveratrol, dexmedetomidine, andketamine. HMGB1-mediated disruption of lysosomal membrane is constrainedby chloroquine phosphate and hydroxychloroquine.

Chloroquine

Chloroquine phosphate-based therapy in China and hydroxychloroquinetreatment in South Korea have been reported to improve outcome inSARS□CoV□2 infections. Gao J, et al., Breakthrough: Chloroquinephosphate has shown apparent efficacy in treatment of COVID-19associated pneumonia in clinical studies, Bioscience trends. 2020.Chloroquine-mediated alkalinization of lysosomes inhibiting HMGB1-causedlysosomal leakage is one plausible mechanism. Intact lysosome functionprevents the activation of multiple proinflammatory cytosolic receptors.Furthermore, chloroquine has been demonstrated to decrease HMGB1secretion from activated innate immunity cells. (Schierbeck H, et al.,Immunomodulatory drugs regulate HMGB1 release from activated humanmonocytes, Molecular Medicine (Cambridge, Mass.). 2010; 16(9-10):343-51(61)).

Based on the fact that HMGB1 operates as a detergent in the acidicconditions in lysosomes (Deng M, et al., The Endotoxin Delivery ProteinHMGB1 Mediates Caspase-11-Dependent Lethality in Sepsis, Immunity, 2018;49(4):740-53.e7 15), it is of distinct clinical interest that recentChinese clinical studies report that chloroquine phosphate therapyexerts beneficial therapeutic effects in SARS-CoV-2 infection (Gao J, etal., Breakthrough: Chloroquine phosphate has shown apparent efficacy intreatment of COVID-19 associated pneumonia in clinical studies,Bioscience Trends, 2020). The drug will be included in officialguidelines for therapy of SARS-CoV-2 in China (Zhonghua jie, Expertconsensus on chloroquine phosphate for the treatment of novelcoronavirus pneumonia, Chinese Journal of Tuberculosis and RespiratoryDiseases, 2020; 43(3):185-8. 38). Chloroquine accumulates in lysosomesand raises the pH, something that counteracts HMGB1 from operating likea detergent in the lysosomes and thus precludes lysosomal leakage ofDAMP molecules to the cytosol.

Heparin

Heparin is a high affinity HMGB1 binding molecule. (Ling Y, et al.,Heparin changes the conformation of high-mobility group protein 1 anddecreases its affinity toward receptor for advanced glycation endproducts in vitro, International Immunopharmacology, 2011; 11(2):187-93:Li L, et al., Heparin inhibits the inflammatory response induced by LPSand HMGB1 by blocking the binding of HMGB1 to the surface ofmacrophages, Cytokine, 2015; 72(1):36-42; Rouhiainen A, et al,Inhibition of Homophilic Interactions and Ligand Binding of the Receptorfor Advanced Glycation End Products by Heparin and Heparin-RelatedCarbohydrate Structures, Medicines (Basel, Switzerland). 2018; 5(3)).The conformation of HMGB1 changes when heparin combines with HMGB1 andthis change inhibits the binding of HMGB1 to the surface of activatedmacrophages. (Ling Y, et al., Heparin changes the conformation ofhigh-mobility group protein 1 and decreases its affinity toward receptorfor advanced glycation endproducts in vitro, InternationalImmunopharmacology, 2011; 11(2):187-93). Heparin-HMGB1 complexes areunable to induce RAGE dimerization that is required for the function ofRAGE. (Rouhiainen A, et al, Inhibition of Homophilic Interactions andLigand Binding of the Receptor for Advanced Glycation End Products byHeparin and Heparin-Related Carbohydrate Structures, Medicines (Basel,Switzerland). 2018; 5(3)). Heparin treatment reduced the lethality inmice exposed to LPS-HMGB1 complexes. (Li L, et al., Heparin inhibits theinflammatory response induced by LPS and HMGB1 by blocking the bindingof HMGB1 to the surface of macrophages, Cytokine, 2015; 72(1):36-42).However, a clinical utilization of heparin as an anti-inflammatory agentcarries a risk of causing life-threatening bleeding. There are modifiedheparin preparations with very low anticoagulant activity that could beconsidered for this purpose, and one such heparinoid compound has beensuccessfully tested in phase I/II studies of Plasmodium falciparummalaria disease in patients. (Leitgeb A M, et al., Inhibition ofmerozoite invasion and transient de-sequestration by sevuparin in humanswith Plasmodium falciparum malaria, PLoS One, 2017; 12(12):e0188754).This molecule also prevented neutrophil-induced lung plasma leakage in amurine sepsis model. (Rasmuson J, et al., Heparinoid sevuparin inhibitsStreptococcus-induced vascular leak through neutralizingneutrophil-derived proteins, Faseb J. 2019; 33(9):10443-52.Neutrophil-mediated pathology is of central importance in acute lunginjury.

Thrombomodulin

Thrombomodulin is an endothelial cell thrombin receptor known to convertthrombin into an anticoagulant. Soluble thrombomodulin also binds toHMGB1 and aids the proteolytic cleavage of HMGB1 by thrombin. (AbeyamaK, et al., The N-terminal domain of thrombomodulin sequestershigh-mobility group-B1 protein, a novel antiinflammatory mechanism, TheJournal of Clinical Investigation. 2005; 115(5):1267-74). There is agreat number of clinical and preclinical reports of successfulthrombomodulin treatment in inflammatory conditions. (Ito T, et al.,Thrombomodulin as an intravascular safeguard against inflammatory andthrombotic diseases, Expert Opin Ther Targets, 2016; 20(2):151-8).Recombinant thrombomodulin is efficaciously used in Japan to treatpatients with disseminated intravascular coagulation in sepsis.(Yamakawa K, et al., Recombinant Human Soluble Thrombomodulin inSepsis-Induced Coagulopathy: An Updated Systematic Review andMeta-Analysis, Thrombosis and Haemostasis, 2019; 119(1):56-65).

Haptoglobin

The major mission of the acute phase protein haptoglobin is to bind andeliminate extracellular hemoglobin, but haptoglobin also capturesextracellular HMGB1. (Yang H, et al., Identification of CD163 as anantiinflammatory receptor for HMGB1-haptoglobin complexes, JCI Insight,2016; 1(7)). Hemorrhage in an inflammatory process will dislocate HMGB1from haptoglobin and fuel inflammation, since haptoglobin has anexceptionally strong affinity for hemoglobin. Haptoglobin-HMGB1complexes bind to CD163 on macrophages activating an anti-inflammatoryresponse mediated via production of IL-10 and heme-oxygenase 1. (Id.)Therapeutic administration of haptoglobin improved septic shock, lunginjury, and survival in an experimental pneumonia model. (Remy K E, etal., Haptoglobin improves shock, lung injury, and survival in caninepneumonia. JCI Insight. 2018; 3(18)). Haptoglobin is approved in Japanto treat patients with trauma, burns, and transfusion-related hemolysis.

Resveratrol

Resveratrol is a phytoalexin phenol molecule acting as a protectiveendogenous antibiotic when produced in plants under stress. Resveratrolsuppresses TLR4 expression (Yang Y, et al., Resveratrol reduces theproinflammatory effects and lipopolysaccharide-induced expression ofHMGB1 and TLR4 in RAW264.7 cells, Cellular Physiology and Biochemistry:International Journal of Experimental Cellular Physiology, Biochemistry,and Pharmacology. 2014; 33(5):1283-92) and both in vitro and in vivostudies demonstrate that resveratrol activates SIRT1 to reduceHMGB1/TLR4/MyD88/NF-κB signaling. (Le K, et al., SIRT1-regulated HMGB1release is partially involved in TLR4 signal transduction: A possibleanti-neuroinflammatory mechanism of resveratrol in neonatalhypoxic-ischemic brain injury, International Immunopharmacology, 2019;75:105779 (73)). These results indicate that resveratrol amelioratesinflammation in part via inhibited HMGB1/TLR4-mediated signaling.

Statins

Statins are used extensively for treatment of cardiovascular diseasesdue to their cholesterol-lowering effects, but they also exertbeneficial anti-inflammatory effects. These effects are partly broughtabout by inhibition of both the HMGB1/TLR4- and HMGB1/RAGE-mediatedpathways. (Liu M, et al., Simvastatin suppresses vascular inflammationand atherosclerosis in ApoE(−/−) mice by downregulating the HMGB1-RAGEaxis, Acta Pharmacologica Sinica, 2013; 34(6):830-6; Wu B, et al.,Short-time pretreatment of rosuvastatin attenuates myocardial ischemiaand reperfusion injury by inhibiting high mobility group box 1 proteinexpression, International Journal of Cardiology, 2013; 168(5):4946-8;Han Q F, et al., Simvastatin protects the heart against ischemiareperfusion injury via inhibiting HMGB1 expression through PI3K/Aktsignal pathways, International Journal of Cardiology, 2015; 201:568-9;Zhu Z, Fang Z, Statin protects endothelial cell against ischemiareperfusion injury through HMGB1/TLR4 pathway, International Journal ofCardiology, 2016; 203:74; Zhang H, et al., Rosuvastatin reduces thepro-inflammatory effects of adriamycin on the expression of HMGB1 andRAGE in rats, International Journal of Molecular Medicine, 2018;42(6):3415-23). The expression of HMGB1, RAGE, and TLR4 were all reducedby statin treatment in different vascular inflammatory diseases.

Glycyrrhizin

Glycyrrhizin is an active component extracted from licorice plant rootsand acts as an HMGB1 antagonist. It is widely utilized in traditionalChinese medicine to treat inflammatory conditions. Glycyrrhizinattenuated pulmonary inflammation, decreased microvascular permeabilityand HMGB1 release in an experimental model of LPS-induced acute lunginjury. (Qu L, et al., Glycyrrhizic acid ameliorates LPS-induced acutelung injury by regulating autophagy through the PI3K/AKT/mTOR pathway,American Journal of Translational Research, 2019; 11(4):2042-55).

Acetylcholine

RAGE-mediated endocytosis of HMGB1 complexes with other proinflammatorymolecules is restrained by acetylcholine, 7 nicotinic acetylcholinereceptor (α7nAChR) agonists, recombinant HMGB1 box A protein, oneanti-HMGB1 mAb (2G7), and dynamin inhibitors as revealed by in vitroexperiments. (Yang H, et al., Inhibition of HMGB1/RAGE-mediatedendocytosis by HMGB1 antagonist box A, anti-HMGB1 antibodies, andcholinergic agonists suppresses inflammation. Molecular Medicine(Cambridge, Mass.). 2019; 25(1):13). Acetylcholine signaling via α7nAChRhas also been reported to protect against LPS-induced acute lung injuryby inhibiting the TLR4/MyD88/NF-κB signaling pathway. (Zi S F, et al.,Dexmedetomidine-mediated protection against septic liver injury dependson TLR4/MyD88/NF-kappaB signaling downregulation partly via cholinergicanti-inflammatory mechanisms, International Immunopharmacology, 2019;76:105898).

Acetylcholine-mediated amelioration of inflammation can be accomplishedby electrical stimulation of the vagus nerve. (Pavlov V A, et al.,Molecular and Functional Neuroscience in Immunity, Annu Rev Immunol,2018; 36:783-812). Surgical implantation of vagus nerve pacemakers hasdemonstrated highly beneficial therapeutical results in rheumatoidarthritis and Crohn's disease. (Koopman F A, et al., Vagus nervestimulation inhibits cytokine production and attenuates disease severityin rheumatoid arthritis, Proceedings of the National Academy of Sciencesof the United States of America, 2016; 113(29):8284-9. (82)). A need forsurgery can be circumvented by transauricular vagus nerve stimulationusing an external pulse generator, which is an inexpensive device meantfor personal use. (Hong G S, et al., Non-invasive transcutaneousauricular vagus nerve stimulation prevents postoperative ileus andendotoxemia in mice, Neurogastroenterology and Motility: the OfficialJournal of the European Gastrointestinal Motility Society, 2019;31(3):e13501). Furthermore, transcutaneous vagus nerve stimulationreduced systemic HMGB1 levels and improved survival in an experimentalsepsis model. (Huston J M, et al., Transcutaneous vagus nervestimulation reduces serum high mobility group box 1 levels and improvessurvival in murine sepsis, Critical Care Medicine, 2007; 35(12):2762-8).

Galantamine

Another approach to confer cholinergic control over inflammation mightbe to use the centrally acting acetylcholinesterase inhibitorgalantamine. (Pavlov V A, et al., Molecular and Functional Neurosciencein Immunity, Annu Rev Immunol, 2018; 36:783-812). Galantamine is inclinical use for counteracting cognitive impairment in Alzheimer'sdisease, but has also been demonstrated to ameliorate inflammation inthe metabolic syndrome. (Consolim-Colombo F M, et al., Galantaminealleviates inflammation and insulin resistance in patients withmetabolic syndrome in a randomized trial, JCI Insight, 2017; 2(14)).

Dexmedetomidine

Dexmedetomidine is a potent α2-adrenergic receptor agonist widely usedfor sedation in intensive care medicine. The compound also reducessystemic proinflammatory cytokine release through the cholinergicanti-inflammatory pathway via a7nAChR-dependent signaling. (Xiang H, etal., Dexmedetomidine controls systemic cytokine levels through thecholinergic anti-inflammatory pathway, Inflammation, 2014;37(5):1763-70). Administration of dexmedetomidine has been demonstratedto increase the discharge frequency of cervical vagus nerves resultingin reduced release of proinflammatory mediators and improved survival inexperimental endotoxemia. (Id.) Histological studies of lung sectionsfrom LPS-induced lung injury revealed reduced expression of TLR4 andHMGB1. (Meng L, et al., The protective effect of dexmedetomidine onLPS-induced acute lung injury through the HMGB-mediated TLR4/NF-kappaBand PI3K/Akt/mTOR pathways, Mol Immunol, 2018; 94:7-17). Furthermore,combined dexmedetomidine-ketamine treatment mitigated pulmonaryinflammatory response induced by ventilator-induced lung injury inendotoxemic rats. (Yang C L, et al., Protective effects ofdexmedetomidine-ketamine combination against ventilator-induced lunginjury in endotoxemia rats, The Journal of Surgical Research. 2011;167(2):e273-81).

Ketamine

Ketamine is another extensively used pharmacological substance inanesthesia and is judged as safe and to facilitate hemodynamicallystable anesthesia or sedation. It also mediates anti-inflammatoryfunctions including inhibition of HMGB1 secretion from activatedmacrophages (89). Furthermore, ketamine has been shown to attenuatesepsis-induced acute lung injury via a functional down-regulation of theHMGB1-RAGE pathway in preclinical studies. (Zhang Y, et al., Ketaminealleviates LPS induced lung injury by inhibiting HMGB-RAGE level,European Review for Medical and Pharmacological Sciences, 2018;22(6):1830-6). Ketamine reduced the recruitment of neutrophils andmonocytes into the inflamed lungs, diminished myeloperoxidase activityand the expression of HMGB1 and TLR4. (Li K, et al., Ketamine attenuatessepsis-induced acute lung injury via regulation of HMGB-RAGE pathways,International Immunopharmacology, 2016; 34:114-28; Qin M Z, et al.,Ketamine effect on HMGB1 and TLR4 expression in rats with acute lunginjury, International Journal of Clinical and Experimental Pathology,2015; 8(10):12943-8). Since SARS-CoV-2 patients with severe ARDS mayneed a long period with ventilator support, ketamine could be consideredto be incorporated into the sedation protocol for these patients.

P5779

A small peptide antagonist, P5779, that inhibits HMGB1 from binding tothe TLR4/MD-2 receptor complex, blocks this signaling and significantlyimproves survival in mice when administered after a lethal dose ofinfluenza (Shirey K A, Novel strategies for targeting innate immuneresponses to influenza, Mucosal Immunol., 2016; 9(5):1173-82). Thispeptide also has therapeutic benefit in mouse models of sepsis and acuteliver toxicity. (Yang H, MD-2 is required for disulfide HMGB1-dependentTLR4 signaling, J Exp Med., 2015; 212(1):5-14).

OBJECTS AND SUMMARY OF THE INVENTION

It is an object of the invention to treat sepsis by targeting HMGB1.

It is an object of the invention to treat sepsis by targeting HMGB1using an HMGB1 antagonist(s) as a therapeutic agent(s) for reducingmortality and rescuing long-lasting sequelae of sepsis.

It is a further object of the invention to treat sepsis by targetingHMGB1 using an HMGB1 antagonist that has a significantly greater invitro and in vivo stability than previously known small molecules ornon-antibody HMGB1 antagonists.

It is a further object of the invention to treat sepsis by targetingHMGB1 using an HMGB1 antagonist that is a peptidomimetic small moleculemodeled after an HMGB1 antagonist tetramer peptide.

It is a further object of the invention to treat sepsis by targetingHMGB1 using an HMGB1 antagonist tetramer peptide which has beenstabilized by azatide linkages.

It is a further object of the invention for the HMGB1 antagonist K883 tobe used in the treatment and/or prevention and/or inhibition of severesepsis in mammals.

It is an object of this invention to develop novel therapeuticapproaches to treat ALI, including influenza-induced ALI, and otherforms of inflammatory disease to reduce morbidity and mortality.

It is an object of the invention to treat ALI by targeting HMGB1.

It is a further objection of the invention is to advance a smallmolecule for reducing mortality and pathology associated with ALI.

It is a further object of the invention to develop a novel therapeuticto restrain the unchecked inflammation that precipitates ALI.

It is a further object of the invention to treat ALI by targeting HMGB1using an HMGB1 antagonist that has a significantly greater in vitro andin vivo stability than previously known small molecules or non-antibodyHMGB1 antagonists.

It is a further object of the present application to evaluatetherapeutic potential of certain HMGB1 antagonists for reducinginfluenza-induced ALI in mice.

It is a further object of the invention to provide treat ALI bytargeting HMGB1 using an HMGB1 antagonist that is a peptidomimetic smallmolecule modeled after an HMGB1 antagonist tetramer peptide.

It is a further object of the invention to treat ALI by targeting HMGB1using an HMGB1 antagonist tetramer peptide which has been stabilized byazatide linkages.

It is a further object of the invention for the HMGB1 antagonist K883 tobe used in the treatment and/or prevention and/or inhibition of ALI inmammals.

It is a further object of the invention to attenuate HMGB1-driveninflammation (e.g., caused by ALI) without impairing the immune responseto microbes.

It is a further object of the invention to provide a novel therapeutictarget, HMGB1/TLR4/MD-2 signaling, for treating acute lung injury, acondition that kills one in three afflicted patients.

It is a further goal to develop a novel therapeutic to restrain theunchecked inflammation that precipitates ALI.

It is an object of this invention to develop novel therapeuticapproaches to treat bacterial and viral respiratory infections such asinfluenza and SARS□CoV□2, to reduce morbidity and mortality.

It is an object of the invention to treat bacterial and viralrespiratory infections such as influenza and SARS□CoV□2 by targetingHMGB1.

It is a further objection of the invention is to advance a smallmolecule for reducing mortality and pathology associated with bacterialand viral respiratory infections such as influenza and SARS□CoV□2.

It is a further object of the invention to develop a novel therapeuticto restrain the unchecked inflammation that precipitates bacterial andviral respiratory infections such as influenza and SARS□CoV□2.

It is a further object of the invention to treat bacterial and viralrespiratory infections such as influenza and SARS□CoV□2 by targetingHMGB1 using an HMGB1 antagonist that has a significantly greater invitro and in vivo stability than previously known small molecules ornon-antibody HMGB1 antagonists.

It is a further object of the present application to evaluatetherapeutic potential of certain HMGB1 antagonists for reducing ALIinduced by bacterial and viral respiratory infections such as influenzaand SARS□CoV□2.

It is a further object of the invention to provide treat bacterial andviral respiratory infections such as influenza and SARS□CoV□2 bytargeting HMGB1 using an HMGB1 antagonist that is a peptidomimetic smallmolecule modeled after an HMGB1 antagonist tetramer peptide.

It is a further object of the invention to treat bacterial and viralrespiratory infections such as influenza and SARS□CoV□2 by targetingHMGB1 using an HMGB1 antagonist tetramer peptide which has beenstabilized by azatide linkages.

It is a further object of the invention for the HMGB1 antagonist K883 tobe used in the treatment and/or prevention and/or inhibition ofbacterial and viral respiratory infections such as influenza andSARS□CoV□2 in mammals.

It is a further object of the invention to attenuate HMGB1-driveninflammation (e.g., caused by bacterial and viral respiratory infectionssuch as influenza and SARS□CoV□2 without impairing the immune responseto microbes.

It is a further object of the invention to provide a novel therapeutictarget, HMGB1/TLR4/MD-2 signaling, for treating bacterial and viralrespiratory infections such as influenza and SARS□CoV□2.

It is a further goal to develop a novel therapeutic to restrain theunchecked inflammation caused by bacterial and viral respiratoryinfections such as influenza and SARS□CoV□2 that precipitates ALI.

It is also an object of the present invention to selectively target aHMGB1 isoform-specific signaling pathway that plays a critical role inthe occurrence and development of Neuropathic Pain for the treatment ofpainful Diabetic Peripheral Neuropathy (DPN). (Agalave N., Spinaldisulfide HMGB1, but not all-thiol HMGB1, induces mechanicalhypersensitivity in a TLR4-dependent manner, Scandinavian Journal ofPain, 2015; 8: 47; Wang Y., Tanshinone H A Attenuates ChronicPancreatitis-Induced Pain in Rats via Downregulation of HMGB1 and TRL4Expression in the Spinal Cord, Pain Physician, 2014; 18(4): E615-628).

It is a further object of the invention to treat neuropathic pain, andin particular DPN, by targeting HMGB1 and the HMGB1 isoform specificsignaling pathway.

It is a further object of the invention to treat neuropathic pain, andin particular DPN, by targeting HMGB1 using an HMGB1 antagonist(s) as atherapeutic agent(s) for reducing painful DPN.

It is also an object of the present invention to treat diabetic patientsin general by targeting HMGB1-mediated inflammatory pathways whichunderlie adipose tissue inflammation, insulin resistance and isletdysfunction in diabetes.

It is a further object of the invention to treat neuropathic pain, andin particular DPN by targeting HMGB1 using an HMGB1 antagonist that hasa significantly greater in vitro and in vivo stability than previouslyknown small molecules or non-antibody HMGB1 antagonists.

It is a further object of the invention to treat neuropathic pain, andin particular DPN by targeting HMGB1 using an HMGB1 antagonist that hasimproved oral bioavailability than previously known HMGB1 antagonists.

It is a further object of the invention to treat neuropathic pain, andin particular DPN by targeting HMGB1 using an HMGB1 antagonist that issuitable for subcutaneous administration.

It is a further object of the invention to treat neuropathy pain, and inparticular DPN, by targeting HMGB1 using an HMGB1 antagonist that is apeptidomimetic small molecule modeled after an HMGB1 antagonist tetramerpeptide.

It is a further object of the invention to treat neuropathic pain, andin particular DPN by targeting HMGB1 using an HMGB1 antagonist tetramerpeptide which has been stabilized by azatide linkages.

It is further object of the invention to develop a K883 derivative withimproved oral bioavailability when compared to K883 (>20%).

It is further object of the invention to develop a K883 derivative withimproved subcutaneous bioavailability when compared to K883.

It is a further object of the invention to define PK parameters ofsubcutaneous K883.

It is a further object of the invention to confirm the mechanism and invivo efficacy of selective HMGB1-TLR4/MD-2 inhibition in diabeticneuropathic pain.

It is a further object of the invention for the HMGB1 antagonist K883 tobe used in the treatment and/or prevention and/or inhibition of painfuldiabetic peripheral neuropathy in mammals.

It is an object of the invention to develop a pharmaceutical compositioncomprising a therapeutically effective amount of a peptidomimeticmolecule.

It is a further object to develop the above pharmaceutical compositionsin an oral dosage form and in a parental dosage form.

It is a further object of the invention for the pharmaceuticalcomposition to be a dosage form selected from the group consisting of anoral dosage form, a parenteral dosage form, a buccal dosage form, asublingual dosage form, a nasal dosage form, an inhaler, a nebulizer, atopical dosage form, a transdermal dosage form and a suppository.

In connection with the above objects and others, the invention isdirected in part to a method of treating and/or preventing and/orinhibition of severe sepsis in a mammal comprising administering to amammal a therapeutically effective amount of a peptidomimetic smallmolecule modeled after an HMGB1 antagonist tetramer peptide. In certainpreferred embodiments, the peptidomimetic small molecule is an HMGB1antagonist tetramer peptide which has been stabilized with at least oneazatide linkage. In further preferred embodiments, the peptidomimeticsmall molecule peptidomimetic small molecule is a modified P5779 whereinthe terminal peptide bonds have been replaced with azatide linkages.Most preferably, the peptidomimetic small molecule is K883.

The invention is also directed, in part, to a method of treating and/orpreventing and/or inhibiting ALI in a mammal comprising administering toa mammal a therapeutically effective amount of a peptidomimetic smallmolecule modeled after an HMGB1 antagonist tetramer peptide. In certainpreferred embodiments, the peptidomimetic small molecule is an HMGB1antagonist tetramer peptide which has been stabilized with at least oneazatide linkage. In further preferred embodiments, the peptidomimeticsmall molecule is a modified P5779 wherein the terminal peptide bondshave been replaced with azatide linkages. Most preferably, thepeptidomimetic small molecule is K883.

The invention is also directed, in part, to a method of treating and/orpreventing and/or inhibiting the adverse consequences of bacterial andviral respiratory infections where increased HMGB1 is implicated, suchas in infections by influenza and/or corona viruses such as SARS□CoV□2,in a mammal comprising administering to a mammal a therapeuticallyeffective amount of a peptidomimetic small molecule modeled after anHMGB1 antagonist tetramer peptide. In certain preferred embodiments, thepeptidomimetic small molecule is an HMGB1 antagonist tetramer peptidewhich has been stabilized with at least one azatide linkage. In furtherpreferred embodiments, the peptidomimetic small molecule is a modifiedP5779 wherein the terminal peptide bonds have been replaced with azatidelinkages. Most preferably, the peptidomimetic small molecule is K883.

The invention is additionally directed, in part, to a method of treatingand/or preventing and/or inhibiting neuropathic pain, and in particular,diabetic peripheral neuropathy (DPN) in a mammal comprisingadministering to a mammal a therapeutically effective amount of apeptidomimetic small molecule modeled after an HMGB1 antagonist tetramerpeptide. In certain preferred embodiments, the peptidomimetic smallmolecule is an HMGB1 antagonist tetramer peptide which has beenstabilized with at least one azatide linkage. In certain preferredembodiments of the invention, the peptidomimetic small molecule is amodified P5779 wherein at least one terminal peptide bond has beenreplaced with an azatide linkage. Most preferably, the peptidomimeticsmall molecule is K883.

The invention is further directed in part to a method of treating and/orpreventing and/or inhibiting neuropathic pain and/or inhibiting, and inparticular, DPN in a mammal comprising administering to a mammal atherapeutically effective amount of a peptidomimetic small moleculemodeled after an HMGB1 antagonist tetramer peptide, wherein thepeptidomimetic small molecule is K883, a derivative of K883 or aderivative of P5779.

The invention is further directed to pharmaceutical compositionscontaining K883. The pharmaceutical compositions may be formulated fororal delivery, parenteral (e.g., intravenous) delivery. In furtherembodiments, the pharmaceutical composition containing K883 may bedesigned for buccal or sublingual delivery, nasal delivery, inhalationor nebulization delivery, topical or transdermal delivery, or as asuppository.

In certain preferred embodiments, a pharmaceutical compositioncontaining a therapeutically effective amount of K883 is administered toa mammal (e.g., human) suffering from severe sepsis. In certain otherpreferred embodiments, a pharmaceutical composition containing atherapeutically effective amount of K883 is administered to a mammal(e.g., human) suffering from ALI. In certain other preferredembodiments, a pharmaceutical composition containing a therapeuticallyeffective amount of K883 is administered to a mammal (e.g., human)suffering from bacterial and/or viral respiratory infections such asinfluenza and SARS□CoV□2. In certain other preferred embodiments, apharmaceutical composition containing a therapeutically effective amountof K883 is administered to a mammal (e.g., human) suffering fromneuropathic pain and in particular diabetic peripheral neuropathy (DPN).The pharmaceutical composition may be administered orally, parenterally(e.g., intravenously, subcutaneously, intramuscularly), or via buccal,intranasal, inhalation or nebulization delivery, transdermal, topical,or sublingual routes, or via suppository.

Certain preferred embodiments of the invention are directed topharmaceutical compositions, the aqueous (water) solubility of the HMGB1antagonist tetramer peptide which has been stabilized with at least oneazatide linkage is greater than about 1 mg/ml. In other preferredembodiments, the aqueous (water) solubility of the HMGB1 antagonisttetramer peptide which has been stabilized with at least one azatidelinkage is greater than about 5 mg/ml.

In certain preferred embodiments of the invention, the HMGB1 antagonisttetramer peptide which has been stabilized with at least one azatidelinkage is stable for greater than 30 minutes, greater than 45 minutesor most preferably greater than 60 minutes in plasma or simulatedstomach acid.

In certain preferred embodiments of the invention, HMGB1 antagonisttetramer peptide is stabilized with at least one azatide linkage andthen is incorporated into an oral pharmaceutical composition.

Certain embodiments of the invention are directed to a method oftreating and/or preventing and/or inhibiting severe sepsis. Certainpreferred embodiments of the invention are directed to a method oftreating and/or preventing and/or inhibiting severe sepsis, in a mammalcomprising administering to a mammal a therapeutically effective amountof a peptidomimetic small molecule modeled after an HMGB1 antagonisttetramer peptide. In preferred embodiments, the peptidomimetic smallmolecule is an HMGB1 antagonist tetramer peptide which has beenstabilized with at least one azatide linkage and in certain preferredembodiments, the peptidomimetic small molecule is a modified P5779. Incertain preferred embodiments, the modified P5779 has at least oneazatide linkage located at a terminal peptide bond. In certain preferredembodiments, the modified P5779 has terminal peptide bonds which havebeen replaced with azatide linkages. In preferred embodiments, thepeptidomimetic small molecule is K883. In certain embodiments, thepeptidomimetic small molecule is a derivative of K883 or P5779. Incertain embodiments of the K883 is combined with an excipient comprisingPBS:PEG 300:propylene glycol:polysorbate 80 at 50:40:5:5. In preferredembodiments, the mammal is a human. In preferred embodiments, the methodof administration is selected from oral delivery, parenteral delivery,buccal delivery, sublingual delivery, nasal delivery, inhalationdelivery, nebulization delivery, topical delivery, transdermal deliveryand suppository delivery. In certain embodiments, the modified P5779 isstable for greater than 60 minutes in plasma or simulated stomach acid.In certain embodiments, the aqueous solubility of the modified P5779 isgreater than about 1 mg/ml and in other embodiments, the aqueoussolubility of the modified P5779 is greater than about 5 mg/ml Incertain preferred embodiments of the invention, the method is atreatment of sepsis, comprising identifying a human patient exhibitingsymptoms of sepsis, and administering K883.

Certain embodiments of the invention are directed to a method oftreatment and/or prevention and/or inhibition comprising treating amammal for a disease or condition selected from the group consisting ofnon-influenza pulmonary infections, smoke or toxic gas inhalation,gastric acid aspiration, transfusion reactions, reactions and injuriescaused by mechanical ventilation arthritis, colitis, sterile ischemia,traumatic injury, cancer and infection, hemorrhagic shock, endotoxemia,gastrointestinal disorders including gastrointestinal inflammation,inflammatory bowel disease such as cecal perforation, intraperitonealLPS injection, and IBD based on chemically induced colitis, respiratorydisorders including sepsis, inflammatory lung injury, acute lung injury,patients subjected to long-term ventilator therapy and cystic fibrosis,autoimmune diseases such as arthritis, dermatomyositis, multiplesclerosis, systemic lupus erythematosus (SLE), celiac disease, chronicfatigue syndrome, Crohn's disease, type 1 diabetes, Graves disease,juvenile arthritis, chronic Lyme disease, myocarditis, myositis,polymyositis, post-myocardial infarction syndrome, psoriasis, psoriaticarthritis, reactive arthritis, rheumatic fever, scleroderma, Sjogren'ssyndrome, thrombocytopenia, ulcerative colitis; neurodegenerativediseases including Alzheimer's, mild cognitive impairment(pre-Alzheimer's), Parkinson's disease, amyotrophic lateral sclerosis(ALS); arthritis including osteoarthritis (OA), arthritic jointinflammation, juvenile idiopathic arthritis (JIA) and serum rheumatoidarthritis (RA); asthma; cancer, including pancreatic cancer, colorectalcancer, skin cancers including melanoma; cardiac and vessel diseaseincluding coronary artery disease (CAD), coronary heart disease, acutecoronary, and atherosclerosis, heart failure; metabolic disordersincluding type 2 diabetes; β-cell transplantation in diabetes; lunginjury and lung related diseases including COPD, pulmonary hypertension,pulmonary fibrosis and pneumonia; Intensive care unit patients beingtreated for various conditions including sepsis, systemic inflammatoryresponse syndrome, severe trauma, blunt chest trauma, hemorrhagicshock/trauma, traumatic brain injury, stroke, spinal cord injury,influenza, chemical toxicity, severe viral or bacterial infections;post-sepsis impairments including cognitive impairments, persistentsplenomegaly, post sepsis anemia; post-surgery neurocognitive disorders;drug induced liver injury including acetaminophen-induced liver injury,ethanol-induced liver diseases, cryopyrin-associated autoinflammatorysyndrome, bleomycin induced lung fibrosis and paracetamol intoxication;nociceptive pain; ischemia (with or without reperfusion), includingcardiac ischemia, cerebral ischemia and skeletal muscle ischemia;inflammatory bowel disease; kidney and liver related disease includingkidney failure and liver failure, hepatic ischemia/reperfusion injury,acute kidney injury (CHD), chronic kidney disease (CKD), acute liverfailure (ALF) including ALF-SIRS and ALF-systemic, liver fibrosis andalcoholic liver disease; trauma/ischemia caused by transplant andgraft-versus-host disease; obesity/metabolic syndrome; pancreatitis;pregnancy complication such as preeclampsia; epilepsy; pulmonaryarterial hypertension (PAH); chronic pain; chronic inflammation; chronicinflammatory diseases including chronic obstructive pulmonary disease(COPD), atherosclerosis and arthritic joint inflammation; and otherdiseases causing moderate to severe pain but not limited topost-surgical pain, fever and inflammation of a variety of conditionsincluding rheumatic fever, symptoms associated with influenza or otherviral infections, common cold, low back and neck pain, dysmenorrhea,headache, toothache, sprains and strains, myositis, neuralgia,synovitis, arthritis, including rheumatoid arthritis, degenerative jointdiseases (osteoarthritis), gout and ankylosing spondylitis, bursitis,burns, and injuries, peptic ulcers, gastritis, regional enteritis,ulcerative colitis, diverticulitis or with a recurrent history ofgastrointestinal lesions; GI bleeding, coagulation disorders includinganemia such as hypoprothrombinemia, hemophilia or other bleedingproblems; kidney disease, chronic fatigue syndrome, traumatic braininjury, concussion and migraines wherein thetreatment/prevention/inhibition comprises administering to the mammal atherapeutically effective amount of a peptidomimetic small moleculemodeled after an HMGB1 antagonist tetramer peptide. Certain preferredembodiments of the invention are directed to a method of treating and/orpreventing and/or inhibiting one of the afore-mentioned diseases, in amammal comprising administering to a mammal a therapeutically effectiveamount of a peptidomimetic small molecule modeled after an HMGB1antagonist tetramer peptide. In preferred embodiments, thepeptidomimetic small molecule is an HMGB1 antagonist tetramer peptidewhich has been stabilized with at least one azatide linkage and incertain preferred embodiments, the peptidomimetic small molecule is amodified P5779. In certain preferred embodiments, the modified P5779 hasat least one azatide linkage located at a terminal peptide bond. Incertain preferred embodiments, the modified P5779 has terminal peptidebonds which have been replaced with azatide linkages. In preferredembodiments, the peptidomimetic small molecule is K883. In certainembodiments, the peptidomimetic small molecule is a derivative of K883or P5779. In certain embodiments of the K883 is combined with anexcipient comprising PBS:PEG 300:propylene glycol:polysorbate 80 at50:40:5:5. In preferred embodiments, the mammal is a human. In preferredembodiments, the method of administration is selected from oraldelivery, parenteral delivery, buccal delivery, sublingual delivery,nasal delivery, inhalation delivery, nebulization delivery, topicaldelivery, transdermal delivery and suppository delivery. In certainembodiments, the modified P5779 is stable for greater than 60 minutes inplasma or simulated stomach acid. In certain embodiments, the aqueoussolubility of the modified P5779 is greater than about 1 mg/ml and inother embodiments, the aqueous solubility of the modified P5779 isgreater than about 5 mg/ml In certain preferred embodiments of theinvention, the method is a treatment for one of the diseases orconditions above, comprising identifying a human patient exhibitingsymptoms of the disease or condition, and administering K883.

Certain embodiments of the invention are directed to a method oftreating, preventing or inhibiting adverse conditions relating tosurgery or the administration of anticoagulants, comprisingadministering to the mammal a therapeutically effective amount of apeptidomimetic small molecule modeled after an HMGB1 antagonist tetramerpeptide prior to the surgery or the administration of theanticoagulants. Certain preferred embodiments of the invention aredirected treating or inhibiting adverse conditions relating to surgeryor the administration of anticoagulants in a mammal comprisingadministering to a mammal a therapeutically effective amount of apeptidomimetic small molecule modeled after an HMGB1 antagonist tetramerpeptide. In preferred embodiments, the peptidomimetic small molecule isan HMGB1 antagonist tetramer peptide which has been stabilized with atleast one azatide linkage and in certain preferred embodiments, thepeptidomimetic small molecule is a modified P5779. In certain preferredembodiments, the modified P5779 has at least one azatide linkage locatedat a terminal peptide bond. In certain preferred embodiments, themodified P5779 has terminal peptide bonds which have been replaced withazatide linkages. In preferred embodiments, the peptidomimetic smallmolecule is K883. In certain embodiments, the peptidomimetic smallmolecule is a derivative of K883 or P5779. In certain embodiments of theK883 is combined with an excipient comprising PBS:PEG 300:propyleneglycol:polysorbate 80 at 50:40:5:5. In preferred embodiments, the mammalis a human. In preferred embodiments, the method of administration isselected from the group consisting of oral delivery, parenteraldelivery, buccal delivery, sublingual delivery, nasal delivery,inhalation delivery, nebulization delivery, topical delivery,transdermal delivery and suppository delivery. In certain embodiments,the modified P5779 is stable for greater than 60 minutes in plasma orsimulated stomach acid. In certain embodiments, the aqueous solubilityof the modified P5779 is greater than about 1 mg/ml and in otherembodiments, the aqueous solubility of the modified P5779 is greaterthan about 5 mg/ml In certain preferred embodiments of the invention,the method is a treatment of adverse conditions relating to surgery orthe administration of anticoagulants, comprising identifying a humanpatient exhibiting symptoms of adverse conditions relating to surgery orthe administration of anticoagulants, and administering K883.

Certain embodiments of the invention are directed to a method oftreating and/or preventing and/or inhibiting ALI. Certain embodiments ofthe invention are directed to a method of treating and/or preventingand/or inhibiting ALI, and in particular reducing influenza-induced ALIin a mammal comprising administering to a mammal a therapeuticallyeffective amount of a peptidomimetic small molecule modeled after anHMGB1 antagonist tetramer peptide. In certain embodiments, thepeptidomimetic small molecule is an HMGB1 antagonist tetramer peptidewhich has been stabilized with at least one azatide linkage. In certainembodiments, the invention is directed to a method for preparing atreatment for acute lung injury, comprising modifying P5779 with atleast one azatide linkage and in certain further embodiments, themodified P5779 has at least one azatide linkage located at a terminalpeptide bond. In certain further embodiments, the modified P5779 isK883. In certain embodiments, the peptidomimetic small molecule is aderivative of K883 or P5779. In certain embodiments, the peptidomimeticsmall molecule is a modified P5779 wherein at least one terminal peptidebond has been replaced with an azatide linkage and in certainembodiments, the peptidomimetic small molecule is a modified P5779wherein the terminal peptide bonds have been replaced with azatidelinkages. In certain embodiments, the mammal is a human. In certainembodiments, the method of administration is selected from the groupconsisting of oral delivery, parenteral delivery, buccal delivery,sublingual delivery, nasal delivery, inhalation delivery, nebulizationdelivery, topical delivery, transdermal delivery and suppositorydelivery. In certain embodiments, the aqueous solubility of the modifiedP5779 is greater than about 1 mg/ml and in other embodiments, theaqueous solubility of the modified P5779 is greater than about 5 mg/ml.In certain embodiments, the modified P5779 is stable for greater than 60minutes in plasma or simulated stomach acid. In certain preferredembodiments, the therapeutically effective amount is orally administeredto the mammal and in other preferred embodiments, the therapeuticallyeffective amount is intravenously administered to the mammal. In certainpreferred embodiments, the peptidomimetic small molecule is K883. Incertain preferred embodiments, the K883 is combined with an excipientcomprising PBS:PEG 300:propylene glycol:polysorbate 80 at 50:40:5:5. Incertain preferred embodiments, the method of treatment of acute lunginjury, comprises identifying a human patient exhibiting symptoms ofacute lung injury, and administering K883.

Certain embodiments of the invention are directed to a method oftreating and/or preventing and/or inhibiting bacterial and viralrespiratory infections such as influenza and SARS□CoV□2 severe sepsis.Certain embodiments of the invention are directed to a method oftreating and/or preventing and/or inhibiting the effects of COVID-19 orother SARS viruses in a mammal comprising administering to a mammal atherapeutically effective amount of a peptidomimetic small moleculemodeled after an HMGB1 antagonist tetramer peptide. In certainembodiments, the peptidomimetic small molecule is an HMGB1 antagonisttetramer peptide which has been stabilized with at least one azatidelinkage. In certain embodiments, the invention is directed to a methodfor preparing a treatment of the effects of COVID-19 or other SARSviruses, comprising modifying P5779 with at least one azatide linkageand in certain further embodiments, the modified P5779 has at least oneazatide linkage located at a terminal peptide bond. In certain furtherembodiments, the modified P5779 is K883. In certain embodiments, thepeptidomimetic small molecule is a derivative of K883 or P5779. Incertain embodiments, the peptidomimetic small molecule is a modifiedP5779 wherein at least one terminal peptide bond has been replaced withan azatide linkage and in certain embodiments, the peptidomimetic smallmolecule is a modified P5779 wherein the terminal peptide bonds havebeen replaced with azatide linkages. In certain embodiments, the mammalis a human. In certain embodiments, the method of administration isselected from the group consisting of oral delivery, parenteraldelivery, buccal delivery, sublingual delivery, nasal delivery,inhalation delivery, nebulization delivery, topical delivery,transdermal delivery and suppository delivery. In certain preferredembodiments, the therapeutically effective amount is orally administeredto the mammal and in other preferred embodiments, the therapeuticallyeffective amount is intravenously administered to the mammal. In certainpreferred embodiments, the peptidomimetic small molecule is K883. Incertain preferred embodiments, the K883 is combined with an excipientcomprising PBS:PEG 300:propylene glycol:polysorbate 80 at 50:40:5:5. Incertain preferred embodiments, the method of treatment of the effects ofCOVID-19 or other SARS viruses, comprises identifying a human patientexhibiting symptoms of COVID-19 or other SARS viruses, and administeringK883. In certain preferred embodiments, the invention is directed to amethod of treating and/or preventing and/or inhibiting bacterial andviral respiratory infections such as influenza and SARS□CoV□2 in amammal comprising administering to a mammal a therapeutically effectiveamount of a peptidomimetic small molecule modeled after an HMGB1antagonist tetramer peptide.

Certain embodiments of the invention are directed to a method oftreating and/or preventing and/or inhibiting of peripheral neuropathy.Certain further embodiments of the invention are directed to theneuropathic pain being diabetic neuropathic pain. In other preferredembodiments, the invention is directed to a method of treating and/orpreventing and/or inhibiting peripheral neuropathy, and in particularDPN in a mammal comprising administering to a mammal a therapeuticallyeffective amount of a peptidomimetic small molecule modeled after anHMGB1 antagonist tetramer peptide. In certain embodiments, thepeptidomimetic small molecule is an HMGB1 antagonist tetramer peptidewhich has been stabilized with at least one azatide linkage. In certainpreferred embodiments the peptidomimetic small molecule is a modifiedP5779 wherein at least one terminal peptide bond has been replaced withan azatide linkage and in certain preferred embodiments, thepeptidomimetic small molecule peptidomimetic small molecule is amodified P5779 wherein the terminal peptide bonds have been replacedwith azatide linkages. In certain preferred embodiments, the inventionis directed to a method of preparing a treatment for neuropathic pain,comprising modifying P5779 with at least one azatide linkage and inother preferred embodiments comprises modifying P5779 with at least oneazatide linkage located at a terminal peptide bond. In certain preferredembodiments, the peptidomimetic small molecule is K883. In certainembodiments, the peptidomimetic small molecule is a derivative of K883or P5779. In certain further embodiments, the K883 is combined with anexcipient comprising PBS:PEG 300:propylene glycol:polysorbate 80 at50:40:5:5. In certain preferred embodiments, the mammal is a human. Inembodiments, the method of administration is selected from the groupconsisting of oral delivery, parenteral delivery, buccal delivery,sublingual delivery, nasal delivery, inhalation delivery, nebulizationdelivery, topical delivery, transdermal delivery and suppositorydelivery. In certain preferred embodiments, the therapeuticallyeffective amount is orally administered to the mammal and in otherpreferred embodiments, the therapeutically effective amount isintravenously administered to the mammal. In certain embodiments, theaqueous solubility of the modified P5779 is greater than about 1 mg/mland in other embodiments, the aqueous solubility of the modified P5779is greater than about 5 mg/ml. In certain embodiments, the modifiedP5779 is stable for greater than 60 minutes in plasma or simulatedstomach acid. In certain preferred embodiments, the invention isdirected to a method of treatment of neuropathic pain, comprisingidentifying a human patient exhibiting symptoms of DPN, andadministering K883.

Certain embodiments of the invention are directed to a pharmaceuticalcomposition comprising a therapeutically effective amount of apeptidomimetic molecule having the chemical structure:

wherein R is C or N; and at least one of R₁ and R₂ is N to provide anazatide linkage, such that the peptidomimetic molecule is stabilizedrelative to a peptidomimetic molecule wherein both R₁ and R₂═C, and atleast one pharmaceutically acceptable excipient. Certain embodiments ofthe present invention are directed to a pharmaceutical composition ofclaim 1, wherein both terminal peptide bonds have been replaced withazatide linkages such that both R₁ and R₂═N and the peptidomimeticmolecule has the structure:

In certain embodiments, the dosage form is selected from the groupconsisting of an oral dosage form, a parenteral dosage form, a buccaldosage form, a sublingual dosage form, a nasal dosage form, an inhaler,a nebulizer, a topical dosage form, a transdermal dosage form and asuppository. In certain preferred embodiments, the pharmaceuticalcomposition is an oral dosage form, an oral liquid dosage form, or aparenteral dosage form. In certain embodiments, the aqueous solubilityof the peptidomimetic molecule is greater than 1 mg/ml and in otherembodiments, the aqueous solubility of the peptidomimetic molecule isgreater than 5 mg/ml. In certain preferred embodiments, thepeptidomimetic molecule is stable for greater than 60 minutes in plasmaor simulated stomach acid. In certain embodiments, the peptidomimeticmolecule is combined with a pharmaceutical excipient selected from thegroup consisting of 1) phosphate buffered saline, 2) PEG, 3) propyleneglycol and 4) polysorbate 80 and 5) combinations thereof. In certainpreferred embodiments, the PEG is PEG 300. In certain embodiments, thepeptidomimetic molecule is combined with a pharmaceutical excipientcomprising PBS:PEG 300:propylene glycol:polysorbate 80 such that theaqueous solubility of peptidomimetic molecule is greater than 1 mg/mland in other embodiments so that the aqueous solubility ofpeptidomimetic molecule is greater than 5 mg/ml. In certain embodiments,the peptidomimetic molecule is combined with a pharmaceutical excipientcomprising PBS:PEG 300:propylene glycol:polysorbate 80 in a ratio ofabout 50:40:5:5.

Certain embodiments of the invention are directed to a pharmaceuticalcomposition comprising a pharmaceutical composition comprising atherapeutically effective amount of a HMGB1 antagonist tetramerpeptidomimetic which has been stabilized with at least one azatidelinkage, and at least one pharmaceutical excipient. In certainembodiments, the HMGB1 antagonist tetramer peptidomimetic has thechemical structure:

wherein R is C or N; and at least one of R₁ and R₂ is N to provide anazatide linkage, such that the HMGB1 antagonist tetramer peptidomimeticis stabilized relative to a HMGB1 antagonist tetramer peptide, P5779, inwhich both R₁ and R₂═C. In other embodiments, the terminal peptide bondshave been replaced with azatide linkages such that both R₁ and R₂═N andthe stabilized HMGB1 antagonist tetramer has the structure:

In certain embodiments, the dosage form is selected from the groupconsisting of an oral dosage form, a parenteral dosage form, a buccaldosage form, a sublingual dosage form, a nasal dosage form, an inhaler,a nebulizer, a topical dosage form, a transdermal dosage form and asuppository. In certain preferred embodiments, the pharmaceuticalcomposition is an oral dosage form, an oral liquid dosage form, or aparenteral dosage form. In certain embodiments, the aqueous solubilityof the peptidomimetic molecule is greater than 1 mg/ml and in otherembodiments, the aqueous solubility of the peptidomimetic molecule isgreater than 5 mg/ml. In certain preferred embodiments, thepeptidomimetic molecule is stable for greater than 60 minutes in plasmaor simulated stomach acid. In certain embodiments, the peptidomimeticmolecule is combined with a pharmaceutical excipient selected from thegroup consisting of 1) phosphate buffered saline, 2) PEG, 3) propyleneglycol and 4) polysorbate 80 and 5) combinations thereof. In certainpreferred embodiments, the PEG is PEG 300. In certain embodiments, thepeptidomimetic molecule is combined with a pharmaceutical excipientcomprising PBS:PEG 300:propylene glycol:polysorbate 80 such that theaqueous solubility of peptidomimetic molecule is greater than 1 mg/mland in other embodiments so that the aqueous solubility ofpeptidomimetic molecule is greater than 5 mg/ml. In certain embodiments,the peptidomimetic molecule is combined with a pharmaceutical excipientcomprising PBS:PEG 300:propylene glycol:polysorbate 80 in a ratio ofabout 50:40:5:5.

In certain preferred embodiments of the invention, the peptidomimeticsmall molecule is an HMGB1 antagonist tetramer peptide which has beenstabilized with at least one azatide linkage. In certain preferredembodiments of the invention, the peptidomimetic small molecule is amodified P5779 wherein at least one terminal peptide bond has beenreplaced with an azatide linkage. In certain preferred embodiments ofthe invention, the peptidomimetic small molecule is a modified P5779wherein the terminal peptide bonds have been replaced with azatide. Incertain preferred embodiments of the invention, the peptidomimetic smallmolecule is K883.

Certain preferred embodiments of the invention are directed to a methodof treatment of severe sepsis, comprising identifying a human patientexhibiting symptoms of severe sepsis, and administering K883. Certainpreferred embodiments of the invention are directed to a method oftreatment of ALI, comprising identifying a human patient exhibitingsymptoms of ALI and administering K883. Certain preferred embodiments ofthe invention are directed to a method of treatment of bacterial andviral respiratory infections such as influenza and SARS□CoV□2,comprising identifying a human patient exhibiting symptoms of abacterial or viral respiratory infection such as influenza andSARS□CoV□2 and administering K883. Certain preferred embodiments of theinvention are directed to a method of treatment of neuropathic pain, andin particular, DPN, comprising identifying a human patient exhibitingsymptoms of peripheral neuropathy, and in particular DPN andadministering K883.

Certain preferred embodiments of the invention are directed to a methodof preparing a treatment for severe sepsis, ALI, bacterial and viralrespiratory infections such as influenza and SARS□CoV□2 or peripheralneuropathy, and in particular DPN, comprising modifying P5779 with atleast one azatide linkage.

Certain preferred embodiments of the invention are directed to a methodof preparing a treatment for severe sepsis, ALI, bacterial and viralrespiratory infections such as influenza and SARS□CoV□2 or peripheralneuropathy, and in particular DPN, comprising modifying P5779 with atleast one azatide linkage wherein the modified P5779 has at least oneazatide linkage located at a terminal peptide bond.

Certain preferred embodiments of the invention are directed to a methodof preparing a treatment for severe sepsis, ALI, bacterial and viralrespiratory infections such as influenza and SARS□CoV□2 or peripheralneuropathy, and in particular DPN, comprising modifying P5779 with atleast one azatide linkage wherein the modified P5779 is K883. In certainembodiments of the invention, the method of administration is selectedfrom the group consisting of oral delivery, parenteral delivery, buccaldelivery, sublingual delivery, nasal delivery, inhalation delivery,nebulization delivery, topical delivery, transdermal delivery andsuppository delivery. In certain preferred embodiments of the invention,the therapeutically effective amount is orally administered to themammal. In certain preferred embodiments of the invention, thetherapeutically effective amount is intravenously administered to themammal. In certain preferred embodiments of the invention, the mammal ishuman. In certain preferred embodiments of the invention, the K883 iscombined with a mixture containing PBS:PEG 300:propyleneglycol:polysorbate 80 at 50:40:5:5.

Certain preferred embodiments of the invention are directed to apharmaceutical composition, comprising a modified P5779 wherein at leastone terminal peptide bond has been replaced with an azatide linkage.Certain preferred embodiments of the invention are directed to apharmaceutical composition, comprising a modified P5779 wherein theterminal peptide bonds have been replaced with azatide linkages. Incertain preferred embodiments of the invention, pharmaceuticalcomposition is a dosage form selected from the group consisting of anoral dosage form, an oral liquid dosage form, a parenteral dosage form,a buccal dosage form, a sublingual dosage form, a nasal dosage form, aninhalation dosage form, a nebulization dosage form, a topical dosageform, a transdermal dosage form and a suppository dosage form. Incertain preferred embodiments of the invention, the pharmaceuticalcomposition is K883 combined with a mixture containing PBS:PEG300:propylene glycol:polysorbate 80 at 50:40:5:5.

In certain embodiments, the HMGB1 antagonist tetramer peptide which hasbeen stabilized with at least one azapeptide linkage is capable ofreducing influenza-induced ALI in mice such that mice treated with apharmaceutical composition containing the HMGB1 antagonist tetramerpeptide which has been stabilized with at least one azapeptide linkagehave a survival greater than 50%, greater than 60% or preferably greaterthan 70%, a reduced lung pathology compared to untreated mice; and/or asignificantly longer time to treatment onset and still achieve rescuesurvival when compared to P5779. In certain embodiments the time totreatment onset with K883 is about 30% longer than the onset timerequired for treatment with P5779 to achieve rescue survival. In certainembodiments the time to treatment onset with K883 is about 35% longerthan the onset time required for treatment with P5779 to achieve rescuesurvival. In certain other embodiments, the time to treatment onset withK883 is more than 40% longer than the onset time required for treatmentwith P5779 to achieve rescue survival.

BRIEF DESCRIPTION OF THE DRAWINGS

The patent or application file contains at least one drawing executed incolor. Copies of this patent or patent application publication withcolor drawing(s) will be provided by the Office upon request and paymentof the necessary fee.

FIG. 1 is a graphical depiction of inflammation induced by HMGB1-partnermolecule complexes.

FIG. 2A is a graphical representation of the proportion of hospitalstays in the United States that carried sepsis as a primary or secondaryindication in 2009.

FIG. 2B is a graphical representation of the percentage costs oftreating sepsis in the United States.

FIG. 3 is a graphical representation of ALI incidence and mortalityacross age cohorts, subdivided by predisposing factors.

FIGS. 4A and 4B are representations of how dysregulated inflammationcauses ALI with FIG. 4A depicting the feedback loop that drivesimmunopathology in ALI and FIG. 4B showing how HMGB1 levels roughlycorrelate with tissue damage and negative outcomes.

FIG. 5 is a graphical representation of the biological effects of HMGB1.

FIGS. 6A-6C shows the three known isoforms of HMGB1.

FIG. 7 is a graphical depiction of approved pharmacological compoundsinhibiting HMGB1-RAGE-TLR4-mediated inflammation.

FIG. 8A is a graphical depiction of the therapeutic properties onpercentage survival of different doses of murine anti-HMGB1 monoclonalantibody, mu-2G7, realized through administration twenty-four hoursafter cecal ligation and puncture sepsis model.

FIG. 8B is a graphical depiction showing rescue of persistent anemiameasured by hemoglobin levels in murine sepsis survivors afterinjections of mu-2G7 on days 9-11 following cecal ligation and puncture.

FIGS. 9A and 9B show HMGB1 in an influenza-induced model of ALI: FIG. 9Ais a graphical representation showing HMGB1 levels following infectionwith Influenza A/PR/8/34 (H1N1) and FIG. 9B is a graphicalrepresentation showing monoclonal anti-HMGB1 rescuing lethalityfollowing H1N1 infection.

FIG. 10A is a graphical depiction showing humanized anti-HMGB1 antibody,hu-2G7 has comparable specificity to mu-2G7.

FIG. 10B is a graphical depiction showing humanized anti-HMGB1monoclonalantibody, hu-2G7 has a higher affinity for HMGB1 than mu-2G7 withaffinities analyzed by Surface Plasmon Resonance (SPR) binding studies,with Langmuir-binding used to determine dissociation constants.

FIG. 11 is a graphical depiction of percentage survival in mice aftertreatment with the peptide P5779 following cecal ligation and punctureas compared to a scrambled control peptide (SFES).

FIGS. 12A and 12B are graphical depictions of inhibition of MD-2 bindingto HMGB1 as measured by SPR binding studies using a Biacore T200©instrument. FIG. 12A demonstrates dose-responsive inhibition achievedwith increasing concentrations of P5779 (0-2000 nM) and thedose-responsive inhibition achieved with increasing concentrations ofK883 (0-2000 nM) is shown in FIG. 12B.

FIG. 13 is a modeling depiction of the azapeptide K883 binding in apocket between the TLR4 receptor and the adaptor protein MD-2. TLR4 andMD-2 protein surfaces are represented in gray and orange, respectivelyand K883 carbon atoms are shown in blue.

FIGS. 14A-14C are graphical depictions showing relative stabilitymeasured by HPLC of the peptide P5779 at time 0 (FIG. 14A) versus 3hours (FIG. 14B) and 6 hours (FIG. 14C) after in vitro incubation withmouse serum.

FIGS. 14D-14F depict azapeptide K883 stability measured by HPLC fromtime 0 (FIG. 14D), at 3 hours (FIG. 14E), and up to 6 hours (FIG. 14F)after in vitro incubation with mouse serum. Relative absorbance isindicated on Y axes while retention times are indicated on x axes.Azapeptide K883 retains structural stability for a longer period of timethan the peptide P5779.

FIGS. 15A-15C are graphical depictions of the inhibition ofHMGB1-induced tumor necrosis factor (TNF) secretion in both human andmouse macrophages. FIG. 15A shows the inhibition achieved withincreasing concentrations of K883 (0-10 μM) in human primary macrophagesand 15B shows the inhibition achieved with P5779 (0-10 μM) in humanprimary macrophages. FIG. 15C shows the inhibition achieved withincreasing concentrations of K883 (0-50 μM) of HMGB1-induced TNFsecretion from mouse macrophages.

FIGS. 16A to 16D are graphical depictions showing PAMP-induced TNFrelease in human macrophages is not inhibited by various concentrationsof K883.

FIGS. 17A-17G display graphs showing TNF secretion induced by variousDAMPs in human macrophages. K883 causes inhibition of HMGB1-induced TNFsecretion (FIG. 17A) but TNF secretion induced by other DAMPs (FIG.17B-17G) is not inhibited by various concentrations of K883 in humanmacrophages.

FIG. 18 is a graphical depiction showing P5779 peptide enhancedpercentage survival in cecal ligation and puncture-sepsis.

FIGS. 19A-F are graphical depictions of effects of P5779 on amelioratinginflammation, lethality, and tissue damage in a mouse model ofAPAP-induced liver injury. FIGS. 19A-D depict the serum inflammatorymarkers, AST (FIG. 19A), ALT (FIG. 19B), TNF (FIG. 19C), and HMGB1 (FIG.19D) after P5779 treatment. FIG. 19E shows increased survival aftertreatment with P5779 but not control scramble peptide, while FIG. 19Fdepicts histology images showing treatment with HMGB1 inhibitor P5779reduced APAP-mediated liver injury.

FIG. 20A shows serum inflammatory markers after P5779 treatment in theAPAP-liver toxicity model, 500 ugs/mouse led to significant reductionsin ALT and FIG. 20B is a graphical depiction showing that treatment with50 ug/mouse of K883 reduced serum ALT in the liver APAP-toxicity model.

FIGS. 21A to 21C are histology images demonstrating that K883 reducesAPAP-induced liver injury in the mouse model. Arrow indicates area ofnecrosis.

FIG. 22 shows improved survival outcome in mice that have beenadministered K883 in the APAP-induced liver injury model.

FIG. 23 is a graphical depiction showing K883 has a longer half-life inserum than P5779 peptide (undetectable).

FIG. 24 is a graphical depiction showing K883 increases the survival offlu virus infected mice compared with P5779 peptide.

FIG. 25 shows that K883 enhanced percentage survival in cecal ligationand puncture-sepsis.

FIG. 26A shows disulfide HMGB1 levels in spinal cord in chronicconstriction injury (CCI) model in rats and FIG. 26B shows neutralizingeffect of anti-HMGB1 antibody (mAb) 2g7.

FIG. 27A and FIG. 27B are graphical depictions showing the effects ofrepeated K883 administration on CCI-induced neuropathic pain. (*: P<0.05vs. CCI phosphate buffered saline group (PBS). N=6 rats/group).

FIGS. 28A-C are graphical depictions showing the effects of P5779 andK883 on streptozotocin (STZ) induced diabetes in mice.

FIG. 29 shows an outline for how to determine the effects of selectiveHMGB1-TLR4/MD-2 inhibition on painful DPN.

FIGS. 30A-30E are graphical depictions showing inhibition by K883 ofdisulfide HMGB1-induced calcium influx in F11 cells.

FIGS. 31A-31C are graphical depictions showing K883 improved CCI-inducedthermal and mechanical hypersensitivity over time in rats.

FIGS. 32A-32C are graphical depictions showing K883 reduces CCI-inducedCXCL1 and TNF expression (DRGs).

FIG. 33A-33D are graphical depictions showing K883 reduces CCI-inducedCXCL1, TNF and IL-1β expression (spine).

FIG. 34 shows the selective activation of Dorsal root ganglia (DRG)sensory neurons by disulfide HMGB1-induced Ca2+ influx.

FIG. 35A is a graphical depiction showing that HMGB1 induces neuropathicpain (mechanical allodynia) in rat paws and FIG. 35B is a graphicaldepiction showing mAb 2g7 ameliorates HMGB1-induced mechanical allodyniain rat paws.

DETAILED DESCRIPTION OF THE INVENTION

In accordance with the above stated objects, it is shown thatadministration of a peptidomimetic small molecule that replaces terminalpeptide bonds with azatide linkages (e.g., K883) to a subject(s) orpatient(s) in need thereof, can prevent and/or inhibit and/or treatsepsis, ALI, bacterial and viral respiratory infections such asinfluenza and SARS□CoV□2 and/peripheral neuropathy, in particular DPN.

The embodiments of the present invention, i.e. a rationally designedpeptidomimetic small molecule, represent a huge advance in targetingHMGB1. Existing HMGB1 “inhibitors” either have numerous additionaltargets (e.g., glycyrrhizin) or only impinge on HMGB1 signalingindirectly (e.g., gabexate mesilate, a serine protease inhibitor). Incontrast, the specificity of targeting distinct aspects of HMGB1signaling allows the possibility of reducing systemic inflammation whilepreserving the immune system's response to pathogens. This selectiveapproach represents a critical feature for treating patients who oftenhave active systemic infections, one that currently available globalimmunosuppressive therapies lack. The specificity of targeting distinctaspects of HMGB1 signaling allows the possibility of ameliorating ALIthrough targeted immunosuppression, as well as the possibility ofameliorating bacterial and viral respiratory infections such asinfluenza and SARS□CoV□2. The specificity of targeting distinct aspectsof HMGB1 signaling also allows the possibility of amelioratingneuropathic pain, and in particular DPN through targetedimmunosuppression.

HMGB1 has been implicated in driving the progression of sepsis by thetwin observations that sepsis severity roughly tracks with levels ofcirculating HMGB1 (Wang, H., et al., HMG-1 as a late mediator ofendotoxin lethality in mice, Science, 1999, 285(5425): p. 248-51; Gibot,S., et al., High-mobility group box 1 protein plasma concentrationsduring septic shock, Intensive Care Med, 2007, 33(8): p. 1347-53;Sunden-Cullberg, J., et al., Persistent elevation of high mobility groupbox-1 protein (HMGB1) in patients with sepsis and septic shock, CritCare Med, 2005, 33(3): p. 564-73) and that the presence of anti-HMGB1autoantibodies correlates with improved outcomes (Barnay-Verdier, S., etal., Emergence of autoantibodies to HMGB1 is associated with survival inpatients with septic shock, Intensive Care Med, 2011, 37(6): p. 957-62).Experiments in rodents have confirmed that HMGB1-mediated signaling iscentral for precipitating the pathogenic inflammation that leads tomortality or other sequelae in sepsis survivors. Sepsis can be inducedin rodents via the cecal ligation and puncture method; it is thepreferred experimental model for sepsis because it recapitulates theprogression of sepsis in humans (Dejager, L., et al., Cecal ligation andpuncture: the gold standard modelfor polymicrobial sepsis?, TrendsMicrobiol, 2011, 19(4): p. 198-208). Briefly, cecal ligation andpuncture surgery involves ligating the cecum to cause necrosis of thebowel and breaching the intestine and extruding a small amount of stoolto establish an active, polymicrobial intra-abdominal infection. Similarto sepsis in humans, the survival rate is between 20% to 40% whenuntreated (Qin, S., et al., Role of HMGB1 in apoptosis-mediated sepsislethality, J Exp Med, 2006, 203(7): p. 1637-42; Yang, H., et al.,Reversing established sepsis with antagonists of endogenoushigh-mobility group box 1, Proc Natl Acad Sci USA, 2004, 101(1): p.296-301) and survivors develop a persistent microcytic, hypochromicanemia (Valdes-Ferrer, S. I., et al., HMGB1 mediates anemia ofinflammation in murine sepsis survivors, Mol Med, 2015). Remarkably,administering HMGB1-neutralizing antibodies, even as late as 24 hourspost-injury, can counteract these symptoms attributed to blockingHMGB1-mediated release of pro-inflammatory cytokines.

As seen from FIG. 8A mice injected with polyclonal anti-HMGB1 sera forthree days following cecal ligation and puncture (Yang, H., et al.,Reversing established sepsis with antagonists of endogenoushigh-mobility group box 1, Proc Natl Acad Sci USA, 2004, 101(1): p.296-301) or with a single dose of purified monoclonal Ab (mu-2G7) at 24hours post-cecal ligation and puncture. (Qin, S., et al., Role of HMGB1in apoptosis-mediated sepsis lethality, J Exp Med, 2006, 203(7): p.1637-42) had significantly lower mortality than mice injected with acontrol IgG that did not react with HMGB1. This is a wide therapeuticwindow relative to other agents that selectively target cytokinemediators of sepsis. Importantly, anti-TNF antibodies worsen survivalfrom sepsis in this model, highlighting the important differencesbetween TNF and HMGB1 and their respective antagonism. In addition, FIG.8B shows that injecting mu-2G7 on days 9-11 post-cecal ligation andpuncture can substantially rescue anemia, measured by hemoglobin levelsin murine sepsis survivors (Valdes-Ferrer, S. I., et al., HMGB1 mediatesanemia of inflammation in murine sepsis survivors, Mol Med, 2015). Thus,HMGB1 antagonists may be efficacious in two distinct therapeuticwindows: at diagnosis to rescue mortality and as a continuous treatmentto alleviate lingering sequelae of sepsis such as anemia and cognitivedecline (Chavan, S. S., et al., HMGB1 mediates cognitive impairment insepsis survivors, Mol Med, 2012, 18: p. 930-7).

HMGB1 is a late mediator of inflammation. In animals, all cellssynthesize HMGB1; healthy cells sequester it in the nucleus, where itserves as a transcription factor. (Andersson U, HMGB1 is a therapeutictarget for sterile inflammation and infection, Annu Rev Immunol., 2011;29:139-62; Wang H, HMG-1 as a late mediator of endotoxin lethality inmice, Science, 1999; 285(5425):248-51) Cellular damage, necrosis, andapoptosis result in the passive release of HMGB1 into the extracellularspace, which can recruit leukocytes to the site of an injury orinfection. In turn, these monocytes, tissue macrophages, and other cellsof the innate immune system actively secrete HMGB1 when activated bypathogen-derived stimuli, exosomes, or pro-inflammatory cytokines.Depending upon its oxidation state and which of its receptors areengaged, extracellular HMGB1 can trigger a variety of outcomes (reviewedin Lotze M T, High-mobility group box 1 protein (HMGB1): nuclear weaponin the immune arsenal Nat Rev Immunol., 2005; 5(4):331-42; Yang H,Targeting HMGB1 in inflammation, Biochim Biophys Acta., 2010;1799(1-2):149-56 and Harris H E, HMGB1: a multifunctional alarmindriving autoimmune and inflammatory disease, Nat Rev Rheumatol., 2012;8(4):195-202), including secretion of additional HMGB1 to sustain theimmune response until the insult is resolved. These characteristics,pro-inflammatory cytokine activity and prolonged release, recommendHMGB1 as an attractive therapeutic target in inflammatory diseases.(Andersson U, HMGB1 is a therapeutic target for sterile inflammation andinfection, Annu Rev Immunol, 2011; 29:139-62).

HMGB1 mediates inflammation during acute lung injury. Intra-trachealinjection of purified HMGB1 causes pulmonary edema, invasion of thealveolar space by macrophages and neutrophils, and a sharp increase inconcentrations of pro-inflammatory cytokines (e.g. TNFα and IL-1β) inlung fluids. (Abraham E, HMG-1 as a mediator of acute lung inflammation,J Immunol., 2000; 165(6):2950-4). In a mouse model of influenza-inducedpneumonia, Nosaka and colleagues observed elevated HMGB1 levels in serumand bronchoalveolar lavage fluid (BALF) (Nosaka N, Anti-high mobilitygroup box-1 monoclonal antibody treatment provides protection againstinfluenza A virus (H1N1)-induced pneumonia in mice, Crit Care, 2015;19:249) Treating influenza-inoculated mice with a neutralizingmonoclonal antibody against HMGB1 reduces inflammation (and innateimmune cell infiltration) and protects against lethality (see FIG. 9).FIGS. 9A and 9B shows HMGB1 in an influenza-induced model of ALI. Asseen in FIG. 9A, HMGB1 levels rise following infection with InfluenzaA/PR/8/34 (H1N1). Serum levels of HMGB1 (black bars) rise throughout theexperiment, while HMGB1 levels in bronchoaleveolar lavage fluid (BALF;orange bars) peak one week after infection. Dotted lines=HMGB1 baseline.As seen in FIG. 9B, monoclonal anti-HMGB1 rescues lethality followingH1N1 infection. FIG. 9B is adapted from Nosaka N, Anti-high mobilitygroup box-1 monoclonal antibody treatment provides protection againstinfluenza A virus (H1N1)-induced pneumonia in mice, Crit Care, 2015;19:249, which shows that remarkably, this therapy does not affect viralclearance.

HMGB1 and its bound molecules have been implicated as mediators in thepathogenesis of influenza and human respiratory syncytial virusinfections, viral conditions sharing distinct clinical features withSARS□CoV□2. Exaggerated host inflammatory response is a major cause oflung damage and subsequent mortality in many severe pulmonaryinflammatory conditions including SARS-CoV-2. An overexcitedHMGB1-RAGE-TLR4 axis can be expected in e.g. SARS-CoV-2 since thenecrotic respiratory epithelial cells will contribute great quantitiesof extracellular HMGB1 and the cognate HMGB1-receptor RAGE isconstitutively abundantly expressed specifically in the lungs. Once thepulmonary inflammation is initiated, a further pulmonary upregulation ofRAGE and TLR4 will be engendered combined with an increased active HMGB1release from innate immunity cells and from the peripheral nervoussystem. A substantial number of preclinical studies demonstrates thatHMGB1 antagonists may ameliorate severe pulmonary inflammationregardless if it is of infectious or sterile origin. In preferredembodiments of the invention, an improved outcome in severe SARS-CoV-2and other severe respiratory virus infections and influenza is achievedby targeting the HMGB1-RAGE-TLR4 route.

No HMGB1-specific mAbs have yet undergone clinical studies, althoughthere are two humanized anti-HMGB1 mAbs successfully studied inpreclinical inflammatory disease models. (Lundback P, et al., A novelhigh mobility group box 1 neutralizing chimeric antibody attenuatesdrug-induced liver injury and postinjury inflammation in mice,Hepatology (Baltimore, Md.), 2016; 64(5):1699-710). However, there arealready approved defined molecules that could be considered to useclinically to inhibit excessive HMGB1 proinflammatory activities inexaggerated pulmonary inflammation (see FIG. 7).

Exaggerated host inflammatory response is a major cause of lung damageand subsequent mortality in many severe pulmonary inflammatoryconditions including SARS-CoV-2. An overexcited HMGB1-RAGE-TLR4 axis canbe expected in SARS-CoV-2 since the necrotic respiratory epithelialcells will contribute great quantities of extracellular HMGB1 and thecognate HMGB1-receptor RAGE is constitutively abundantly expressedspecifically in the lungs. Once the pulmonary inflammation is initiated,a further pulmonary upregulation of RAGE and TLR4 will be engenderedcombined with an increased active HMGB1 release from innate immunitycells and from the peripheral nervous system. A substantial number ofpreclinical studies demonstrates that HMGB1 antagonists may amelioratesevere pulmonary inflammation regardless if it is of infectious orsterile origin.

The mAb mu-2G7 was evaluated as a basis of interest for developing abiologic intervention to neutralize HMGB1. The mu-2G7 antibodyrecognizes an epitope in the A-box DNA-binding domain of HMGB1 thatallows it to differentiate between HMGB1 and the closely related proteinHMGB2; it binds to HMGB1 irrespective of the protein's oxidation stateand blocks all known biological activity for each isoform (Lundback, P.,et al., A novel high mobility group box 1 neutralizing chimeric antibodyattenuates drug-induced liver injury and postinjury inflammation inmice, Hepatology, 2016, 64(5): p. 1699-1710; Yang, H., et al., Acritical cysteine is required for HMGB1 binding to Toll-like receptor 4and activation of macrophage cytokine release, Proc Natl Acad Sci USA,2010, 107(26): p. 11942-7; Venereau, E., et al., Mutually exclusiveredox forms of HMGB1 promote cell recruitment or proinflammatorycytokine release, J Exp Med, 2012, 209(9): p. 1519-28); and itantagonizes HMGB1 independent of complement activation or any Fcinteractions (Knezevic, I., H. N. Kang, and R. Thorpe, Immunogenicityassessment of monoclonal antibody products: A simulated case studycorrelating antibody induction with clinical outcomes, Biologicals,2015, 43(5): p. 307-17). However, murine antibodies are not suitable forclinical use because their immunogenicity in humans can blunt theirtherapeutic efficacy and even create safety problems (Id.). Tocircumvent these limitations, Lundback and colleagues constructed achimeric antibody by fusing the variable domains of 2G7 with humanconstant (Fc) domains of the IgG1 isotype (Lundback, P., et al., A novelhigh mobility group box 1 neutralizing chimeric antibody attenuatesdrug-induced liver injury and postinjury inflammation in mice,Hepatology, 2016, 64(5): p. 1699-1710). This architecture is analogousto that used to create infliximab (Remicade), an analogous chimericmouse-human monoclonal antibody (Elliott, M. J., et al., Randomiseddouble-blind comparison of chimeric monoclonal antibody to tumournecrosis factor alpha (cA2) versus placebo in rheumatoid arthritis,Lancet, 1994, 344(8930): p. 1105-10; Taylor, P. C. and M. Feldmann,Anti-TNF biologic agents: still the therapy of choice for rheumatoidarthritis, Nat Rev Rheumatol, 2009, 5(10): p. 578-82). The firstanti-TNF mAb launched for clinical use, Infliximab has during the latesttwo decades been a tremendous clinical success to alleviate rheumatoidarthritis and inflammatory bowel diseases (IBD) administered to morethan 2 million patients. Hence, humanized anti-HMGB1 based on mu-2G7 isindicated to work very well over long periods of time (Monaco, C., etal., Anti-TNF therapy: past, present and future, Int Immunol, 2015,27(1): p. 55-62).

FIG. 10A is a graphical depiction that shows that the humanizedanti-HMGB1 antibody, called hu-2G7, retains the same specificity asmu-2G7 while displaying a slightly higher affinity than the murineantibody. FIG. 10B is a graphical depiction showing humanizedanti-HMGB1monoclonal antibody hu-2G7 has a higher affinity for HMGB1than mu-2G7 with affinities analyzed by Surface Plasmon Resonance (SPR)binding studies, with Langmuir-binding used to determine dissociationconstants. Functionally, hu-2G7 has been tested in a mouse model ofacetaminophen-induced (APAP) acute liver injury, a highlyHMGB1-dependent inflammatory condition, where it provided an equivalenttherapeutic benefit to mu-2G7 (Lundback, P., et al., A novel highmobility group box 1 neutralizing chimeric antibody attenuatesdrug-induced liver injury and postinjury inflammation in mice,Hepatology, 2016, 64(5): p. 1699-1710).

A large body of in vivo and in vitro data attests to the effectivenessof HMGB1 neutralizing antibodies to reduce inflammation, yet thewholesale inactivation of HMGB1 signaling may be suboptimal in somecontexts. HMGB1 facilitates inflammation in response tolipopolysaccharide (LPS) and other PAMPs. (Tsung, A., S. Tohme, and T.R. Billiar, High-mobility group box-1 in sterile inflammation, J InternMed, 2014, 276(5): p. 425-43); for patients with active infections, itmay be desirable to conserve HMGB1-mediated responses to PAMPs.Furthermore, in some contexts HMGB1 signaling has an anti-inflammatoryeffect. For example, HMGB1 complexed with haptoglobin binds CD163 tostimulate the release of anti-inflammatory cytokines, and the severityof cecal ligation and puncture sepsis is exacerbated in CD163 orhaptoglobin mutants (Yang, H., et al., Identification of CD163 as anantiinflammatory receptor for HMGB1-haptoglobin complexes, JCI Insight,2016, 1(7). Hence, the present invention is directed to a refinedstrategy for limiting HMGB1-driven inflammation by interfering withbinding between HMGB1 and its receptors. The first indication of thefeasibility of this approach came with the observation that injectingmice with a purified fragment of HMGB1, the A-box domain, protectedagainst lethality after cecal ligation and puncture (Yang, H., et al.,Reversing established sepsis with antagonists of endogenoushigh-mobility group box 1, Proc Natl Acad Sci USA, 2004, 101(1): p.296-301).

Although HMGB1 is purported to interact with as many as 15 distinctreceptor systems, several considerations strongly suggest that thetoll-like receptor TLR4 is one of the main functional receptor systems(Yang, H., et al., A critical cysteine is required for HMGB1 binding toToll-like receptor 4 and activation of macrophage cytokine release, ProcNatl Acad Sci USA, 2010, 107(26): p. 11942-7). Thus, Toll-like ReceptorTLR4 has emerged as the primary pro-inflammatory signaling receptor forHMGB1 in numerous disorders in which HMGB1 has been implicated,including hemorrhagic shock, ischemia/reperfusion injury, sepsis, andothers. (Apetoh L, The interaction between HMGB1 and TLR4 dictates theoutcome of anticancer chemotherapy and radiotherapy, Immunol Rev. 2007;220:47-59; Apetoh L, Toll-like receptor 4-dependent contribution of theimmune system to anticancer chemotherapy and radiotherapy, Nat Med.,2007; 13(9):1050-9; Fan J, Li Y, Hemorrhagic shock induces NAD(P)Hoxidase activation in neutrophils: role of HMGB1-TLR4 signaling, JImmunol., 2007; 178(10):6573-80. Tsung A, HMGB1 release induced by liverischemia involves Toll-like receptor 4 dependent reactive oxygen speciesproduction and calcium-mediated signaling, J Exp Med., 2007;204(12):2913-23; Zong M, TLR4 as receptor for HMGB1 induced muscledysfunction in myositis, Ann Rheum Dis., 2013; 72(8):1390-9).

Extracellular HMGB1 is incapable of activating NF-κB, a hallmark ofHMGB1 signaling, when TLR4 is absent or functionally blocked (Yang, H.,et al., MD-2 is required for disulfide HMGB1-dependent TLR4 signaling, JExp Med, 2015, 212(1): p. 5-14; Yang, H., et al., A critical cysteine isrequired for HMGB1 binding to Toll-like receptor 4 and activation ofmacrophage cytokine release, Proc Natl Acad Sci USA, 2010, 107(26): p.11942-7). HMGB1 also has a striking capacity to complex with a greatmany other inflammatory molecules, including LPS and other PAMPs,inflammatory cytokines, and danger-associated molecular patterns (DAMPs)that signify injury and cellular damage. A majority of the reportedreceptors likely recognize these partner molecules rather than HMGB1 perse (Hreggvidsdottir, H. S., et al., High mobility group box protein 1(HMGB)-partner molecule complexes enhance cytokine production bysignaling through the partner molecule receptor, Mol Med, 2012, 18: p.224-30). In contrast, the complex of TLR4 and the adaptor protein MD-2specifically bind “free” (i.e., uncomplexed) HMGB1 and signal throughMYD88- or TRIF-dependent pathways, ultimately leading to NF-κBactivation. Therefore, the focus of the present invention is thedisruption of the signaling through the TLR4/MD-2/HMGB1 axis.

Yang and colleagues identified a tetrameric peptide (P5779) thatantagonizes the interaction between HMGB1 and MD-2, blocking activationof the toll-like receptor TLR4 and the release of pro-inflammatorycytokines. (Yang, H., et al., MD-2 is required for disulfideHMGB1-dependent TLR4 signaling, J Exp Med, 2015, 212(1): p. 5-14). P5779seems to isolate and attenuate HMGB1-driven inflammation withoutimpairing the immune response to pathogens. It does not inhibitpathogen-stimulated cytokine release in vitro or in vivo. (Yang H, MD-2is required for disulfide HMGB1-dependent TLR4 signaling, J Exp Med.,2015; 212(1):5-14). It is protective in a diverse array of in vivomodels, reducing mortality in models of ischemia/reperfusion injury,acetaminophen toxicity, and sepsis, underscoring the importance ofHMGB1/MD-2/TLR4 as the major pro-inflammatory signaling axis in thesemodels. Id. Significantly, in a mouse model of influenza-induced ALI andlethality, P5779 reduces mortality approximately 9-fold in mice whengiven daily for five days beginning two days after influenza infection(see FIG. 11 which shows P5779 rescues survival after lethal influenzainfection with strain PR8), and it lowers clinical scores in survivors.(Shirey K A, Novel strategies for targeting innate immune responses toinfluenza, Mucosal Immunol., 2016; 9(5):1173-82).

In FIG. 11, the survival advantage of injecting the peptide followingcecal ligation and puncture is shown to confer a survival advantage whencompared to a scrambled control peptide (SFES) which does not confer asurvival advantage. Although P5779 diminished cytokine release frommacrophages exposed to recombinant HMGB1, it did not inhibitLPS-stimulated cytokine release in vitro or in vivo. This is notattributable to low in vivo activity, however, since repeat doses of thepeptide reduced mortality in models of ischemia/reperfusion injury,acetaminophen toxicity, cecal ligation and puncture-induced sepsis (Id.)and acute lung injury (Shirey, K. A., et al., Novel strategies fortargeting innate immune responses to influenza, Mucosal Immunol, 2016,9(5): p. 1173-82). Thus, P5779 allows TLR4/MD-2/HMGB1-driveninflammation to be attenuated without impairing the immune response tomicrobes. And thus, in one instance P5779 administration bluntsHMGB1-mediated activation of the TLR4/MD-2 signaling pathway anddiminishes HMGB1-induced release of pro-inflammatory cytokines frommacrophages.

Many studies have also demonstrated that disulfide isoform of HMGB1 canselectively interact with Toll-like receptor 4 (TLR4) to induce cytokineproduction. (Yang H., Redox modification of cysteine residues regulatesthe cytokine activity of high mobility group box-1 (HMGB1), MolecularMedicine, 2012; 18(1): 250; Yang H., MD-2 is required for disulfideHMGB1-dependent TLR4 signaling, J Exp Med, 2015:jem. 20141318; Yang H.,The many faces of HMGB1: molecular structure-functional activity ininflammation, apoptosis, and chemotaxis, Journal of Leukocyte Biology,2013; 93(6): 865-873; Ma F., Disulfide high mobility group box-1 causesbladder pain through bladder Toll-like receptor 4, BMC physiology, 2017;17(1): 6). Given the vital role of TLR4 in neuropathic pain, (Agalave N.M., Spinal HMGB1 induces TLR4-mediated long-lasting hypersensitivity andglial activation and regulates pain-like behavior in experimentalarthritis, PAIN®, 2014; 155(9): 1802-1813; Liu T., Emerging role ofToll-like receptors in the control of pain and itch, Neurosciencebulletin, 2012; 28(2): 131-144; Li Y., Toll-like receptor 4 signalingcontributes to Paclitaxel-induced peripheral neuropathy, The Journal ofPain, 2014; 15(7): 712-725; Kim D., Toll-like receptors in peripheralnerve injury and neuropathic pain, Toll-like Receptors: Roles inInfection and Neuropathology: Springer, 2009: 169-186; Guo L-H, Theinnate immunity of the central nervous system in chronic pain: the roleof Toll-like receptors, Cellular and Molecular Life Sciences, 2007;64(9): 1128), the evidence that TLR4 is elevated in diabetic rodents,(Yan J-e, Streptozotocin-induced diabetic hyperalgesia in rats isassociated with upregulation of toll-like receptor 4 expression,Neuroscience letters, 2012; 526(1): 54-58; Zhu T., Toll-like receptor 4and tumor necrosis factor-alpha as diagnostic biomarkers for diabeticperipheral neuropathy, Neuroscience Letters, 2015; 585: 28-32) andpatients, (Zhu T., TLR4 and Caveolin-1 in Monocytes Are Associated WithInflammatory Conditions in Diabetic Neuropathy, Clinical andTranslational Science, 2017; 10(3): 178-184) and certain TLR4 genepolymorphism is associated with reduced risk of diabetic neuropathy inhumans (Rudofsky G., Asp299Gly and Thr399Ile genotypes of the TLR4 geneare associated with a reduced prevalence of diabetic neuropathyinpatients with type 2 diabetes, Diabetes Care, 2004; 27(1): 179-183),it is a goal of this invention to develop a therapy targeting disulfideHMGB1/TLR-4 signaling pathway to result in a novel, safe, and effectivestrategy for the treatment of NP and particularly of painful DPN.(Agalave N., Spinal disulfide HMGB1, but not all-thiol HMGB1, inducesmechanical hypersensitivity in a TLR4-dependent manner, ScandinavianJournal of Pain, 2015; 8: 47; Wang Y, Tanshinone IIA Attenuates ChronicPancreatitis-Induced Pain in Rats via Downregulation of HMGB1 and TRL4Expression in the Spinal Cord, Pain Physician, 2014; 18(4): E615-628).

It is also a goal of this invention to develop a peptidomimetic smallmolecule for selectively targeting an HMGB1 isoform-specific signalingpathway that plays a critical role in the occurrence and development ofneuropathic pain. It is a further goal of this invention to advance anHMGB1 inhibitor that can selectively bind to TLR4 adaptor molecule,myeloid differentiation factor 2 (MD-2), which is required for disulfideHMGB1-dependent TLR4 signaling. (Yang H., MD-2 is required for disulfideHMGB1-dependent TLR4 signaling, J Exp Med, 2015: jem. 20141318). Thereare no other drugs in development or clinical use that exhibit thisnovel mechanism of action.

The most studied HMGB1 inhibitor is the neutralizing monoclonalanti-HMGB1 mAb 2g7, which does not discriminate isoforms of HMGB1 (seeTable 1). It is known that haptoglobin (a serum hemoglobin bindingprotein) β subunit binds HMGB1 (disulfide and fully reduced). (Yang H.,Haptoglobin (Beta) Subunit Binds and Sequesters Hmgb1 Toxicity, Paperpresented at: SHOCK2016; Yang H., The haptoglobin beta subunitsequesters HMGB1 toxicity in sterile and infectious inflammation,Journal of Internal Medicine, (2017)).

TABLE 1 mAb 2g7 binds to all isoforms of HMGB1 HMGB1 isoform Kd (M) tomAb 2g7 Disulfide 1.0 × 10⁻⁸ Fully reduced 4.6 × 10⁻⁸ Sulfonyl 1.2 ×10⁻⁸

Although it was known that TLR4 signaling depends on the co-receptorMD-2, (Vail J., Novel roles of lysines 122, 125, and 58 in functionaldifferences between human and murine MD-2, The Journal of Immunology,2009; 183(8): 5138-5145; Visintin A., MD-2, Immunobiology, 2006; 211(6):437-447), it was not known how the TLR4 receptor distinguished betweenHMGB1 isoforms. It is now understood that MD-2 is required forHMGB1-TLR4 signaling and that MD-2 binds specifically to thecytokine-inducing disulfide HMGB1, to the exclusion of other isoforms.(Yang H., MD-2 is required for disulfide HMGB1-dependent TLR4 signaling,J Exp Med., 2015; 212(1): 5-14).

Based on the critical role of Cys106 in dictating HMGB1/MD-2 interactionand TLR4 signaling, and the understanding that disulfide HMGB1-dependentTLR4 signaling is the key and dominant mechanism underlying thegeneration of cytokines, (Yang H., Redox modification of cysteineresidues regulates the cytokine activity of high mobility group box-1(HMGB1), Molecular Medicine, 2012; 18(1): 250; Yang H., The many facesof HMGB1: molecular structure-functional activity in inflammation,apoptosis, and chemotaxis, Journal of Leukocyte Biology, 2013; 93(6):865-873), Yang and colleagues developed a tetrameric peptide (P5779)that is a disulfide HMGB1-specific inhibitor. P5779 has been shown toprevent MD-2-HMGB1 interaction and subsequent TLR4 signaling,effectively binding to MD-2 with relatively potent affinity (Kd=0.65 μM)(and without binding to HMGB1 or TLR4 in the absence of MD-2), toinhibit HMGB1-induced TNF release from macrophages in aconcentration-dependent manner and to not suppress TNF release inmacrophages stimulated by lipopolysaccharide (LPS, TLR4 agonist),peptidoglycan (PGN, TLR2), Poly I:C (TLR3), CpG DNA (TLR9) or S100 A12(RAGE). (Yang H., MD-2 is required for disulfide HMGB1-dependent TLR4signaling, J Exp Med., 2015; 212(1): 5-14). It is protective in adiverse array of in vivo models, reducing mortality in models ofischemia/reperfusion injury, acetaminophen toxicity, and sepsis,underscoring the importance of HMGB1/MD-2/TLR4 as the majorpro-inflammatory signaling axis in these models. (Id.). Significantly,in a mouse model of influenza-induced ALI and lethality, P5779 reducesmortality approximately 9-fold in mice when given daily for five daysbeginning two days after influenza infection (see FIG. 11 which showsP5779 rescues survival after lethal influenza infection with strainPR8), and it lowers clinical scores in survivors. (Shirey K A, Novelstrategies for targeting innate immune responses to influenza, MucosalImmunol., 2016; 9(5):1173-82).

As a result, P5779 is a potent TLR4/MD-2 inhibitor that selectivelyblocks disulfide HMGB1-mediated inflammation without causingimmune-suppression as it does not inhibit LPS-TLR4 signaling. (Yang H.,MD-2 is required for disulfide HMGB-dependent TLR4 signaling, J Exp Med,2015:jem. 20141318). Although P5779 diminished cytokine release frommacrophages exposed to recombinant HMGB1, it did not inhibitLPS-stimulated cytokine release in vitro or in vivo. This is notattributable to low in vivo activity, however, since repeat doses of thepeptide reduced mortality in models of ischemia/reperfusion injury,acetaminophen toxicity, cecal ligation and puncture-induced sepsis (Id.)and acute lung injury (Shirey, K. A., et al., Novel strategies fortargeting innate immune responses to influenza, Mucosal Immunol, 2016,9(5): p. 1173-82). Thus, P5779 allows TLR4/MD-2/HMGB1-driveninflammation to be attenuated without impairing the immune response tomicrobes. Thus, in one instance P5779 administration bluntsHMGB1-mediated activation of the TLR4/MD-2 signaling pathway anddiminishes HMGB1-induced release of pro-inflammatory cytokines frommacrophages.

The potential to attenuate HMGB1-driven inflammation without impairingthe immune response to microbes, and the wide therapeutic window HMGB1has shown in other indications, make HMGB1 antagonists superb candidatesfor treating a broad range of inflammatory syndromes, including sepsis,ALI and DPN. Yet P5779 is a poor therapeutic candidate due to theminimal plasma stability and short in vivo half-life, which likely wouldnecessitate unfeasible dosing and frequency in the clinical setting.

The present invention is directed, in part, to peptidomimetic smallmolecules which overcome the clinical deficiencies of P5779. Moreparticularly, the present invention is directed to a method of treatingand/or preventing and/or inhibiting severe sepsis in a mammal comprisingadministering to a mammal a therapeutically effective amount of apeptidomimetic small molecule modeled after an HMGB1 antagonist tetramerpeptide, P5779. In certain preferred embodiments, the peptidomimeticsmall molecule is an HMGB1 antagonist tetramer peptide which has beenstabilized with at least one azapeptide linkage. In certain preferredembodiments of the invention, the peptidomimetic small molecule is amodified P5779 wherein at least one terminal peptide bond has beenreplaced with an azapeptide linkage and in other further preferredembodiments, both of the terminal peptide bonds have been replaced withazapeptide linkages.

The present invention is also directed to a method for reducingmortality and pathology associated with ALI, and a method of restrainingthe unchecked inflammation that precipitates ALI. HMGB1 is a therapeutictarget for sterile inflammation and infection. Annual Review Immunol,2011; 29:139-62. It is released by injured or infected cells andspecifically activates immunocompetent cells to release pro-inflammatorycytokines that recruit additional innate immune cells. As a latemediator of inflammation, inhibiting HMGB1 activity has a more amenabletherapeutic window than other pro-inflammatory signals.

The present invention is directed in part to peptidomimetic smallmolecules which overcome the clinical deficiencies of P5779. Moreparticularly, the present invention is directed to a method of treatingand/or preventing and/or inhibiting acute lung injury in a mammalcomprising administering a therapeutically effective amount of apeptidomimetic small molecule modeled after an HMGB1 antagonist tetramerpeptide. In certain preferred embodiments, the peptidomimetic smallmolecule is an HMGB1 antagonist tetramer peptide which has beenstabilized with at least one azatide linkage. In further preferredembodiments, the peptidomimetic small molecule is a modified P5779wherein at least one terminal peptide bond has been replaced with anazatide linkage and in other preferred embodiments, both of the terminalpeptide bonds have been replaced with azatide linkages.

The present invention is also directed, in part, to small molecules thatare structural mimics of peptides that interfere with pro-inflammatorysignaling initiated by HGMB1, an alarmin and a primary late mediator ofinflammation. (Andersson U, HMGB1 is a therapeutic target for sterileinflammation and infection, Annu. Rev. Immunol, 2011; 29:139-62; HarrisH E, HMGB1: a multifunctional alarmin driving autoimmune andinflammatory disease, Nat. Rev. Rheumatol., 2012; 8(4):195-202; Lotze MT, High-mobility group box 1 protein (HMGB1): nuclear weapon in theimmune arsenal, Nat Rev Immunol., 2005; 5(4):331-42; Yang H, TargetingHMGB1 in inflammation, Biochim Biophys Acta., 2010; 1799(1-2):149-56).Certain preferred embodiments of the invention are directed to a smallmolecule that is a structural mimic of a previously described peptidethat interferes with pro-inflammatory signaling initiated by HGMB1.HMGB1 activates the inflammatory response through the TLR4 receptorafter binding to the TLR4 co-receptor, MD2. TLR4/MD2 has been implicatedin ALI. (Imai Y, Identification of oxidative stress and Toll-likereceptor 4 signaling as a key pathway of acute lung injury, Cell, 2008;133(2):235-49; Martin T R, A TRIFfic perspective on acute lung injury,Cell, 2008; 133(2):208-10; Shirey K A, Novel strategies for targetinginnate immune responses to influenza, Mucosal Immunol., 2016;9(5):1173-82; Shirey K A, The TLR4 antagonist Eritoran protects micefrom lethal influenza infection, Nature, 2013; 497(7450):498-502).Notably, by antagonizing the inflammatory cascade that drives ALI, thisnovel new small molecule inhibitor has the potential to be an effectivetherapy for ALI irrespective of the triggering insult.

The present invention is also directed, in part, to peptidomimetic smallmolecules which overcome the clinical deficiencies of P5779. Moreparticularly, the present invention is directed to a method of treatingand/or preventing and/or inhibiting neuropathic pain, and in particularDPN in a mammal comprising administering to a mammal a therapeuticallyeffective amount of a peptidomimetic small molecule modeled after anHMGB1 antagonist tetramer peptide. In certain preferred embodiments, thepeptidomimetic small molecule is an HMGB1 antagonist tetramer peptidewhich has been stabilized with at least one azatide linkage. In certainpreferred embodiments of the invention, the peptidomimetic smallmolecule is a modified P5779 wherein at least one terminal peptide bondhas been replaced with an azatide linkage and in other further preferredembodiments both of the terminal peptide bonds have been replaced withazatide linkages.

The present invention is also directed to a pharmaceutical compositioncomprising a therapeutically effective amount of a peptidomimeticmolecule having the chemical structure:

wherein R is C or N; and at least one of R₁ and R₂ is N to provide anazatide linkage, such that the peptidomimetic molecule is stabilizedrelative to a peptidomimetic molecule wherein both R₁ and R₂═C, and atleast one pharmaceutically acceptable excipient. In certain furtherembodiments, both terminal peptide bonds have been replaced with azatidelinkages such that both R₁ and R₂═N and the peptidomimetic molecule hasthe structure:

In certain preferred embodiments, the invention is directed to apeptidomimetic small molecule, referred to herein as “K883”. Similar toP5779, K883 was shown to bind to MD-2 and also the TLR4:MD-2 complex(data not shown) and to inhibit HMGB1 binding using surface plasmonresonance (SPR) technology. The SPR (Biacore T200) analysis of (A) P5779and (B) K883 inhibition of HMGB1-MD-2 binding can be seen in FIG. 12.Also, K883 docking and molecular dynamic simulations were revealed to besimilar to P5779 (data not shown).

The compounds of the present invention can be prepared by the methodsdescribed in Applicant's co-pending U.S. application Ser. No.16/869,692, filed May 8, 2020 hereby incorporated by reference in itsentirety.

To create K883, the terminal peptide bonds of P5779 were replaced withazapeptide linkages. The structures of P5779 and of K883 can be seenbelow, with the azapeptide linkages which distinguish K883 in bold.

K883 has shown increased potency to prevent MD-2 binding to disulfideHMGB1 (IC₅₀=90 nM) and also has extended in vivo half-life (T1/2>60min). K883 also effectively reduces peripheral neuropathy in a ratchronic constriction injury of the sciatic nerve (CCI) model.

K883 shows significantly higher in vitro and in vivo stability thanP5779. In rat plasma and whole blood, the half-life for degradation ofP5779 was 12 and 13 minutes, respectively. In contrast, K883 was notdegraded after incubating 120 minutes in rat plasma and blood. FollowingIV administration to rats, the plasma half-life of P5779 was <5 minuteswhile for K883 it was 1.2+/−0.2 hours (n=3 animals/experiment). K883 andP5779 have similar MD-2-binding affinity. The experiments discussedbelow test K883's activity to protect mice following cecal ligation andpuncture. K883 mimics the well-characterized peptide P5779 to antagonizeHMGB1 signaling through the TLR4/MD-2 receptor, but with significantlylonger in vivo half-life than the peptide.

FIG. 13 is a modeling depiction of azapeptide K883 binding in a pocketbetween the TLR4 receptor and the adaptor protein MD-2. The K883 bindsat the interface area of TLR4/MD-2 complex with the N-terminal(Phenylalanine residue) anchoring in the MD-2 hydrophobic pocket and theC-terminal (glutamic acid residue) binding to TLR4. The C-terminalcarboxylic acid groups can form salt bridges with the Lys362 and Arg264on the TLR4. Other hydrogen bonds involve Asn339 on TLR4 and Glu92,Val93, Tyr102, Ser118 on MD-2. The phenyl side chain on the P5779N-terminal stabilized the molecule into the MD-2 by forming Pi-piinteraction with Phe76 inside the hydrophobic pocket. FIG. 8A, FIG. 8Band FIG. 11 show a tetrameric peptide antagonist of HMGB1 rescuessurvival following cecal ligation and puncture.

K883 binds MD-2 and is functionally active in vitro similar to P5779 andexhibits a serum half-life >1 hour. This improvement allows forlower/less frequent dosing to achieve comparable or superior outcomes tothose achieved with P5779.

K883 represents an unprecedented opportunity to prevent/treat/inhibitthe pathogenic inflammation that leads to mortality or other sequelae(eg. ALI) in sepsis survivors through targeted immunosuppression. HMGB1is a central mediator in the inflammatory cascade. HMGB1-mediatedsignaling is central for precipitating the pathogenic inflammation thatleads to mortality or other sequelae in sepsis survivors. Furthermore,K883 antagonizes HMGB1 pro-inflammatory signaling specifically throughthe TLR4/MD-2 receptor, which has long been implicated in ALI. (Imai Y,Identification of oxidative stress and Toll-like receptor 4 signaling asa key pathway of acute lung injury, Cell, 2008; 133(2):235-49; Shirey KA, The TLR4 antagonist Eritoran protects mice from lethal influenzainfection, Nature, 2013; 497(7450):498-502; PMCID: PMC3725830). Bydiminishing HMGB1 signaling rather than abolishing it, K883 has theability to dampen the inflammatory response to avoid immunopathologywithout blocking the body's ability to clear pathogens.

R

By virtue of the understanding of the present invention, it is now knownthat now known that HMGB1-dependent TLR4 signaling is the key anddominant mechanism underlying the generation of cytokines (Yang H, etal., Redox modification of cysteine residues regulates the cytokineactivity of high mobility group box-1, (HMGB), Molecular Medicine, 2012;18(1):250; Yang H., et al., The many faces of HMGB1: molecularstructure-functional activity in inflammation, apoptosis, andchemotaxis, Journal of Leukocyte Biology, 2013; 93(6):865-873); 2)dorsal root ganglia (DRG) sensory neurons are selectively activated byHMGB1-induced Ca2+ influx; 3) potent MD-2 ligands (K883) have beensynthesized; 4) the novel HMGB1-TLR4/MD2 inhibitor (K883) selectivelyblocks HMGB1-mediated inflammation without causing immune-suppression asit does not inhibit LPS-TLR4 signaling (Yang H, et al., MD-2 is requiredfor disulfide HMGB1-dependent TLR4 signaling, J Exp Med, 2015:jem,20141318; 5) K883 exhibits increased potency to prevent MD-2 binding todisulfide HMGB1 (IC50=90 nM) and extended in vivo half-life (T1/2=1.5hr); 6) K883 effectively reduces peripheral neuropathy in a rat chronicconstriction injury (CCI) model.

K883 represents a promising treatment for e.g. sepsis, ALI, bacterialand viral respiratory infections such as influenza and SARS-CoV-2 andperipheral neuropathy that is independent of the instigating pathogen,insult, or injury.

Additional Clinical Applications

Furthermore, given the central role HMGB1 plays in inflammation andinnate immune activation, it is likely that the HMGB1 antagonisttetramer peptide which has been stabilized with at least one azapeptidelinkage will find clinical application for a much wider range ofindications beyond ALI resulting from acute respiratory infection causedby influenza and ALI triggers such as sepsis, non-influenza pulmonaryinfections, smoke or toxic gas inhalation, gastric acid aspiration andtreatments for ALI such as transfusion reactions and mechanicalventilation which can cause additional airway injury that exacerbatesthe condition. For example, HMGB1 has been directly implicated inregulating innate and adaptive immunity in health and during arthritis,colitis, sterile ischemia, traumatic injury, cancer and infection. (UlfAndersson, HMGB1 is a Therapeutic Target for Sterile Inflammation andInfection, Annu. Rev. Immunol., 2011, 29:139-62). Further possibleindications could include treatment of hemorrhagic shock, endotoxemia,gastrointestinal disorders including gastrointestinal inflammation,inflammatory bowel disease such as cecal perforation, intraperitonealLPS injection, and IBD based on chemically induced colitis, respiratorydisorders including sepsis, inflammatory lung injury, acute lung injury,patients subjected to long-term ventilator therapy and cystic fibrosis,autoimmune diseases such as arthritis, dermatomyositis, multiplesclerosis, systemic lupus erythematosus (SLE), celiac disease, chronicfatigue syndrome, Crohn's disease, type 1 diabetes, Graves disease,juvenile arthritis, chronic Lyme disease, myocarditis, myositis,polymyositis, post-myocardial infarction syndrome, psoriasis, psoriaticarthritis, reactive arthritis, rheumatic fever, scleroderma, Sjogren'ssyndrome, thrombocytopenia, ulcerative colitis; neurodegenerativediseases including Alzheimer's, mild cognitive impairment(pre-Alzheimer's), Parkinson's disease, amyotrophic lateral sclerosis(ALS); arthritis including osteoarthritis (OA), arthritic jointinflammation, juvenile idiopathic arthritis (JIA) and serum rheumatoidarthritis (RA); asthma; cancer, including pancreatic cancer, colorectalcancer, skin cancers including melanoma; cardiac and vessel diseaseincluding coronary artery disease (CAD), coronary heart disease, acutecoronary, and atherosclerosis, heart failure; metabolic disordersincluding type 2 diabetes; β-cell transplantation in diabetes; lunginjury and lung related diseases including COPD, pulmonary hypertension,pulmonary fibrosis and pneumonia; Intensive care unit patients beingtreated for various conditions including sepsis, systemic inflammatoryresponse syndrome, severe trauma, blunt chest trauma, hemorrhagicshock/trauma, traumatic brain injury, stroke, spinal cord injury,influenza, chemical toxicity, severe viral or bacterial infections; postsepsis impairments including cognitive impairments, persistentsplenomegaly, post sepsis anemia; post-surgery neurocognitive disorders;drug induced liver injury including acetaminophen-induced liver injury,ethanol-induced liver diseases, cryopyrin-associated autoinflammatorysyndrome, bleomycin induced lung fibrosis and paracetamol intoxication;nociceptive pain; ischemia (with or without reperfusion), includingcardiac ischemia, cerebral ischemia and skeletal muscle ischemia;inflammatory bowel disease; kidney and liver related disease includingkidney failure and liver failure, hepatic ischemia/reperfusion injury,acute kidney injury (CHD), chronic kidney disease (CKD), acute liverfailure (ALF) including ALF-SIRS and ALF-systemic, liver fibrosis andalcoholic liver disease; trauma/ischemia caused by transplant andgraft-versus-host disease; obesity/metabolic syndrome; pancreatitis;pregnancy complication such as preeclampsia; epilepsy; pulmonaryarterial hypertension (PAH); chronic pain; chronic inflammation; chronicinflammatory diseases including chronic obstructive pulmonary disease(COPD), atherosclerosis and arthritic joint inflammation; and otherdiseases causing moderate to severe pain but not limited topost-surgical pain, fever and inflammation of a variety of conditionsincluding rheumatic fever, symptoms associated with influenza or otherviral infections, common cold, low back and neck pain, dysmenorrhea,headache, toothache, sprains and strains, myositis, neuralgia,synovitis, arthritis, including rheumatoid arthritis, degenerative jointdiseases (osteoarthritis), gout and ankylosing spondylitis, bursitis,burns, and injuries, peptic ulcers, gastritis, regional enteritis,ulcerative colitis, diverticulitis or with a recurrent history ofgastrointestinal lesions; GI bleeding, coagulation disorders includinganemia such as hypoprothrombinemia, hemophilia or other bleedingproblems; kidney disease; chronic fatigue syndrome, traumatic braininjury, concussion and migraines; those prior to surgery or takinganticoagulants. (Id.; Sonya VanPatten, High Mobility Group Box-1(HMGb1): Current Wisdom and Advancement as a Potential Drug TargetMiniperspective, J. Med. Chem, Dec. 21, 2017, pp. 3-4; DamienBertheloot, HMGB1, IL-1α, IL-33 and S100 proteins: dual-functionalarmins, Cellular & Molecular Immunology (2016), 13, 1-22; A. Tsung,High-mobility group box-1 in sterile inflammation, Journal of InternalMedicine, 2014, 276, 425-443; Ulf Andersson, Extracellular HMGB1 as atherapeutic target in inflammatory diseases, Expert Opin Ther Targets,2018 March; 22(3), 263-277; Ulf Andersson, High-mobility group box 1protein (HMGB1) operates as an alarmin outside as well as inside cells,Semin Immunol, 2018 Mar. 9, pii: 51044-5323(17)30076-3; Sangeeta SChavan, HMGB1 Mediates Cognitive Impairment in Sepsis Survivors,Molecular Medicine, 18: 930-937 (2012); Li Fu, Therapeutic effects ofanti-HMGB1 monoclonal antibody on pilocarpine-induced status epilepticusin mice, Scientific Reports, 7: 1179 (2017); Peter Lundback, A NovelHigh Mobility Group Box 1 Neutralizing Chimeric Antibody AttenuatesDrug-Induced Liver Injury and Postinjury Inflammation in Mice,Hepatology, Vol. 64, No. 5 (2016); Taylor M Parker, The Danger Zone:Systematic Review Of The Role Of Hmgb1 Danger Signaling In TraumaticBrain Injury, Brain Inj., 31(1): 2-8 (2017); Matteo Santoro, In-vivoevidence that high mobility group box 1 exerts deleterious effects inthe 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine model and Parkinson'sdisease which can be attenuated by glycyrrhizin, Neurobiology ofDisease, 91, pp. 59-68 (2016); Karatas H, et al. Spreading depressiontriggers headache by activating neuronal Panx1 channels, Science, 2013,339(6123):1092-5) has implicated HMGB1 and migraine aura and headache;TBI/concussion: A recent review in Neuron has implicated HMGb1 and itsreceptor RAGE in this condition. (Jassam, Y, et al. Neuroimmunology ofTraumatic Brain Injury: Time for a Paradigm Shift, Neuron, 2017,95(6):1246-1265)

The therapeutically effective amount of a peptidomimetic small moleculemodeled after an HMGB1 antagonist tetramer peptide (e.g. a modifiedP5779) is administered to a mammal (e.g. a human) in a suitable dosageform. The suitable dosage form may be administered, e.g. via oraldelivery, parenteral delivery, buccal delivery, sublingual delivery,nasal delivery, inhalation delivery, nebulization delivery, topicaldelivery, transdermal delivery and suppository delivery. In certainembodiments, the oral dosage form is a suitable controlled or sustainedrelease formulation. In certain embodiments, the dosage form is an oralliquid dosage form. In certain preferred formulations, the release ofthe peptidomimetic small molecule occurs in the intestinal tract.

In certain dosage forms, the active agent will be a modified P5779having a terminal peptide bonds replaced with azatide linkages andpreferably the composition is K883. In certain embodiments, the activeagent (e.g. K883) is combined with an excipient selected from the groupconsisting of 1) phosphate buffered saline, 2) PEG, 3) propylene glycoland 4) polysorbate 80 and 5) combinations thereof. In certainembodiments, the active agent (e.g. K883) is combined with an excipientcomprising PBS:PEG 300:propylene glycol:polysorbate 80 at 50:40:5:5. Inpreferred formulations, the aqueous solubility of the modified P5579used as the active ingredient is greater than about 1 mg/ml. In otherpreferred formulations, the aqueous solubility of the modified P5579used as the active ingredient is greater than about 5 mg/ml. In furtherpreferred formulations, the modified P5579 used as the active ingredientis stable for greater than 60 minutes in plasma or simulated stomachacid.

A therapeutically effective amount of the active agent will beadministered in a suitable pharmaceutical composition for the treatmentand/or prevention and/or inhibition of an autoimmune or inflammatorydisease or condition. The pharmaceutical composition can be administeredto a patient in need of treatment for e.g. severe sepsis, acute lunginjury, neuropathic pain, including DPN in a mammal (e.g. a human). Thepharmaceutical composition can also be administered for the treatmentand/or prevention and/or inhibition of the effects of bacterial andviral respiratory infections such as influenza and SARS-CoV-2. Thepharmaceutical composition can also be administered for the treatmentand/or prevention and/or inhibition of adverse conditions relating tosurgery or the administration of anticoagulants.

A pharmaceutical composition of the invention may be prepared, packaged,or sold in bulk, as a single unit dose, or as a plurality of single unitdoses. As used herein, a “unit dose” is discrete amount of thepharmaceutical composition comprising a predetermined amount of theactive ingredient. The amount of the active ingredient is generallyequal to the dosage of the active ingredient which would be administeredto a subject or a convenient fraction of such a dosage such as, forexample, one-half or one-third of such a dosage.

The composition of the invention may consist of the active ingredientalone, in a form suitable for administration to a (human) subject orpatient, or the composition may comprise at least one active ingredientand one or more pharmaceutically acceptable excipients.

In one embodiment, the compositions of the invention are formulatedusing one or more pharmaceutically acceptable carriers. Pharmaceuticallyacceptable carriers that are useful, include, but are not limited to,glycerol, water, saline, ethanol and other pharmaceutically acceptablesalt solutions such as phosphates and salts of organic acids. Examplesof these and other pharmaceutically acceptable carriers are described inRemington's Pharmaceutical Sciences (1991, Mack Publication Co., NewJersey). The carrier may be a solvent or dispersion medium containing,for example, water, ethanol, polyol (for example, glycerol, propyleneglycol, and liquid polyethylene glycol, and the like), suitable mixturesthereof, and vegetable oils.

Formulations may be employed in admixtures with conventional excipients,i.e., pharmaceutically acceptable organic or inorganic carriersubstances suitable for oral, vaginal, parenteral, nasal, intravenous,subcutaneous, enteral, or any other suitable mode of administration,known to the art. The pharmaceutical preparations may be sterilized andif desired mixed with auxiliary agents, e.g., lubricants, preservatives,stabilizers, wetting agents, emulsifiers, salts for influencing osmoticpressure buffers, coloring, flavoring and/or aromatic substances and thelike. They may also be combined where desired with other active agents,e.g., other analgesic agents.

As used herein, “additional ingredients” include, but are not limitedto, one or more of the following: excipients; surface active agents;dispersing agents; inert diluents; granulating and disintegratingagents; binding agents; lubricating agents; sweetening agents; flavoringagents; coloring agents; preservatives; physiologically degradablecompositions such as gelatin; aqueous vehicles and solvents; oilyvehicles and solvents; suspending agents; dispersing or wetting agents;emulsifying agents, demulcents; buffers; salts; thickening agents;fillers; emulsifying agents; antioxidants; antibiotics; antifungalagents; stabilizing agents; and pharmaceutically acceptable polymeric orhydrophobic materials. Other “additional ingredients” that may beincluded in the pharmaceutical compositions of the invention are knownin the art and described, for example in Genaro, ed. (1985, Remington'sPharmaceutical Sciences, Mack Publishing Co., Easton, Pa.), which isincorporated herein by reference.

The composition of the invention may comprise a preservative from about0.005% to 2.0% by total weight of the composition. The preservative isused to prevent spoilage in the case of exposure to contaminants in theenvironment. Examples of preservatives useful in accordance with theinvention included but are not limited to those selected from the groupconsisting of benzyl alcohol, sorbic acid, parabens, imidurea andcombinations thereof.

The composition may include an anti-oxidant and a chelating agent thatinhibits the degradation of the compound. Examples of antioxidants forsome compounds are BHT, BHA, alpha-tocopherol and ascorbic acid in thepreferred range of about 0.01% to 0.3% and more preferably BHT in therange of 0.03% to 0.1% by weight by total weight of the composition.Preferably, the chelating agent is present in an amount of from 0.01% to0.5% by weight by total weight of the composition. Chelating agentsinclude edetate salts (e.g. disodium edetate) and citric acid in theweight range of about 0.01% to 0.20% and more preferably in the range of0.02% to 0.10% by weight by total weight of the composition. Thechelating agent is useful for chelating metal ions in the compositionthat may be detrimental to the shelf life of the formulation. While BHTand disodium edetate are the particularly preferred antioxidant andchelating agent respectively for some compounds, other suitable andequivalent antioxidants and chelating agents may be substitutedtherefore as would be known to those skilled in the art.

Liquid suspensions may be prepared using conventional methods to achievesuspension of the active ingredient in an aqueous or oily vehicle.Aqueous vehicles include, for example, water, and isotonic saline. Oilyvehicles include, for example, almond oil, oily esters, ethyl alcohol,vegetable oils such as arachis, olive, sesame, or coconut oil,fractionated vegetable oils, and mineral oils such as liquid paraffin.Liquid suspensions may further comprise one or more additionalingredients including, but not limited to, suspending agents, dispersingor wetting agents, emulsifying agents, demulcents, preservatives,buffers, salts, flavorings, coloring agents, and sweetening agents. Oilysuspensions may further comprise a thickening agent. Known suspendingagents include, but are not limited to, sorbitol syrup, hydrogenatededible fats, sodium alginate, polyvinylpyrrolidone, gum tragacanth, gumacacia, and cellulose derivatives such as sodium carboxymethylcellulose,methylcellulose, hydroxypropylmethylcellulose. Known dispersing orwetting agents include, but are not limited to, naturally occurringphosphatides such as lecithin, condensation products of an alkyleneoxide with a fatty acid, with a long chain aliphatic alcohol, with apartial ester derived from a fatty acid and a hexitol, or with a partialester derived from a fatty acid and a hexitol anhydride (e.g.,polyoxyethylene stearate, heptadecaethyleneoxycetanol, polyoxyethylenesorbitol monooleate, and polyoxyethylene sorbitan monooleate,respectively). Known emulsifying agents include, but are not limited to,lecithin, and acacia. Known preservatives include, but are not limitedto, methyl, ethyl, or n-propyl para hydroxybenzoates, ascorbic acid, andsorbic acid. Known sweetening agents include, for example, glycerol,propylene glycol, sorbitol, sucrose, and saccharin. Known thickeningagents for oily suspensions include, for example, beeswax, hardparaffin, and cetyl alcohol.

Liquid solutions of the active ingredient in aqueous or oily solventsmay be prepared in substantially the same manner as liquid suspensions,the primary difference being that the active ingredient is dissolved,rather than suspended in the solvent. As used herein, an “oily” liquidis one which comprises a carbon-containing liquid molecule and whichexhibits a less polar character than water. Liquid solutions of thepharmaceutical composition of the invention may comprise each of thecomponents described with regard to liquid suspensions, it beingunderstood that suspending agents will not necessarily aid dissolutionof the active ingredient in the solvent. Aqueous solvents include, forexample, water, and isotonic saline. Oily solvents include, for example,almond oil, oily esters, ethyl alcohol, vegetable oils such as arachis,olive, sesame, or coconut oil, fractionated vegetable oils, and mineraloils such as liquid paraffin.

Powdered and granular formulations of a pharmaceutical preparation ofthe invention may be prepared using known methods. Such formulations maybe administered directly to a subject, used, for example, to formtablets, to fill capsules, or to prepare an aqueous or oily suspensionor solution by addition of an aqueous or oily vehicle thereto. Each ofthese formulations may further comprise one or more of dispersing orwetting agent, a suspending agent, and a preservative. Additionalexcipients, such as fillers and sweetening, flavoring, or coloringagents, may also be included in these formulations.

Controlled- or sustained-release formulations of a composition of theinvention may be made using conventional technology, in addition to thedisclosure set forth elsewhere herein. In some cases, the dosage formsto be used can be provided as slow or controlled-release of one or moreactive ingredients therein using, for example,hydropropylmethylcellulose, other polymer matrices, gels, permeablemembranes, osmotic systems, multilayer coatings, microparticles,liposomes, or microspheres or a combination thereof to provide thedesired release profile in varying proportions. Suitablecontrolled-release formulations known to those of ordinary skill in theart, including those described herein, can be readily selected for usewith the compositions of the invention.

For oral administration, particularly suitable are tablets, dragees,liquids, drops, capsules, caplets and gelcaps. Other formulationssuitable for oral administration include, but are not limited to, apowdered or granular formulation, an aqueous or oily suspension, anaqueous or oily solution, a paste, a gel, toothpaste, a mouthwash, acoating, an oral rinse, or an emulsion. The compositions intended fororal use may be prepared according to any method known in the art andsuch compositions may contain one or more inert, non-toxicpharmaceutically excipients. Such excipients include, for example aninert diluent such as lactose; granulating and disintegrating agentssuch as cornstarch; binding agents such as starch; and lubricatingagents such as magnesium stearate. The oral compositions of theinvention in the form of tablets or capsules prepared by conventionalmeans with pharmaceutically acceptable excipients such as bindingagents; fillers; lubricants; disintegrates; or wetting agents.

Tablets may be non-coated or they may be coated using known methods toachieve delayed disintegration in the gastrointestinal tract of asubject, thereby providing sustained release and absorption of theactive ingredient. By way of example, a material such as glycerylmonostearate or glyceryl distearate may be used to coat tablets. Furtherby way of example, tablets may be coated using methods described in U.S.Pat. Nos. 4,256,108; 4,160,452; and U.S. Pat. No. 4,265,874 to formosmotically controlled release tablets. Tablets may further comprise asweetening agent, a flavoring agent, a coloring agent, a preservative,or some combination of these in order to provide for pharmaceuticallyelegant and palatable preparation. For oral administration, If desired,the tablets may be coated using suitable methods and coating materialssuch as OPADRY® film coating systems available from Colorcon, WestPoint, Pa. (e.g., OPADRY® OY Type, OYC Type, Organic Enteric OY-P Type,Aqueous Enteric OY-A Type, OY-PM Type and OPADRY® White, 32K18400).

Hard capsules comprising the active ingredient may be made using aphysiologically degradable composition, such as gelatin. Such hardcapsules comprise the active ingredient, and may further compriseadditional ingredients including, for example, an inert solid diluentsuch as calcium carbonate, calcium phosphate, or kaolin. Soft gelatincapsules comprising the active ingredient may be made using aphysiologically degradable composition, such as gelatin. Such softcapsules comprise the active ingredient, which may be mixed with wateror an oil medium such as peanut oil, liquid paraffin, or olive oil.

Liquid preparation for oral administration may be in the form ofsolutions, syrups or suspensions. The liquid preparations may beprepared by conventional means with pharmaceutically acceptableadditives such as suspending agents (e.g., sorbitol syrup, methylcellulose or hydrogenated edible fats); emulsifying agent (e.g.,lecithin or acacia); non-aqueous vehicles (e.g., almond oil, oily estersor ethyl alcohol); and preservatives (e.g., methyl or propylpara-hydroxy benzoates or sorbic acid). Liquid formulations of apharmaceutical composition of the invention which are suitable for oraladministration may be prepared, packaged, and sold either in liquid formor in the form of a dry product intended for reconstitution with wateror another suitable vehicle prior to use.

A tablet comprising the active ingredient may, for example, be made bycompressing or molding the active ingredient, optionally with one ormore additional ingredients. Compressed tablets may be prepared bycompressing, in a suitable device, the active ingredient in afree-flowing form such as a powder or granular preparation, optionallymixed with one or more of a binder, a lubricant, an excipient, a surfaceactive agent, and a dispersing agent. Molded tablets may be made bymolding, in a suitable device, a mixture of the active ingredient, apharmaceutically acceptable carrier, and at least sufficient liquid tomoisten the mixture. Pharmaceutically acceptable excipients used in themanufacture of tablets include, but are not limited to, inert diluents,granulating and disintegrating agents, binding agents, and lubricatingagents. Known dispersing agents include, but are not limited to, potatostarch and sodium starch glycollate. Known surface-active agentsinclude, but are not limited to, sodium lauryl sulphate. Known diluentsinclude, but are not limited to, calcium carbonate, sodium carbonate,lactose, microcrystalline cellulose, calcium phosphate, calcium hydrogenphosphate, and sodium phosphate. Known granulating and disintegratingagents include, but are not limited to, corn starch and alginic acid.Known binding agents include, but are not limited to, gelatin, acacia,pre-gelatinized maize starch, polyvinylpyrrolidone, and hydroxypropylmethylcellulose. Known lubricating agents include, but are not limitedto, magnesium stearate, stearic acid, silica, and talc.

As used herein, “parenteral administration” of a pharmaceuticalcomposition includes any route of administration characterized byphysical breaching of a tissue of a subject and administration of thepharmaceutical composition through the breach in the tissue. Parenteraladministration thus includes, but is not limited to, administration of apharmaceutical composition by injection of the composition, byapplication of the composition through a surgical incision, byapplication of the composition through a tissue-penetrating non-surgicalwound, and the like. In particular, parenteral administration iscontemplated to include, but is not limited to, intraocular,intravitreal, subcutaneous, intraperitoneal, intramuscular, intrasternalinjection, intratumoral, and kidney dialytic infusion techniques.

Formulations of a pharmaceutical composition suitable for parenteraladministration comprise the active ingredient combined with apharmaceutically acceptable carrier, such as sterile water or sterileisotonic saline. Such formulations may be prepared, packaged, or sold ina form suitable for bolus administration or for continuousadministration. Injectable formulations may be prepared, packaged, orsold in unit dosage form, such as in ampules or in multi dose containerscontaining a preservative. Formulations for parenteral administrationinclude, but are not limited to, suspensions, solutions, emulsions inoily or aqueous vehicles, pastes, and implantable sustained-release orbiodegradable formulations. Such formulations may further comprise oneor more additional ingredients including, but not limited to,suspending, stabilizing, or dispersing agents. In one embodiment of aformulation for parenteral administration, the active ingredient isprovided in dry (i.e. powder or granular) form for reconstitution with asuitable vehicle (e.g. sterile pyrogen free water) prior to parenteraladministration of the reconstituted composition.

A pharmaceutical composition of the invention may be prepared, packaged,or sold in a formulation suitable for topical administration. There areseveral advantages to delivering compounds, including drugs or othertherapeutic agents, into the skin (dermal drug delivery) or into thebody through the skin (transdermal drug delivery). Transdermal compounddelivery offers an attractive alternative to injections and oralmedications.

Additional dosage forms of this invention include dosage forms asdescribed in U.S. Pat. Nos. 6,340,475; 6,488,962; 6,451,808; 5,972,389;5,582,837 and 5,007,790. Additional dosage forms of this invention alsoinclude dosage forms as described in U.S. Patent Applications Nos.20030147952, 20030104062, 20030104053, 20030044466, 20030039688, and20020051820. Additional dosage forms of this invention also includedosage forms as described in PCT Applications Nos. WO 03/35041, WO03/35040, WO 03/35029, WO 03/35177, WO 03/35039, WO 02/96404, WO02/32416, WO 01/97783, WO 01/56544, WO 01/32217, WO 98/55107, WO98/11879, WO 97/47285, WO 93/18755, and WO 90/11757.

Additional diseases that may be treated and/or prevented and/orinhibited using the pharmaceutical composition of the present inventioninclude autoimmune diseases such as non-influenza pulmonary infections,smoke or toxic gas inhalation, gastric acid aspiration, transfusionreactions, reactions and injuries caused by mechanical ventilation,arthritis, colitis, sterile ischemia, traumatic injury, cancer andinfection, hemorrhagic shock, endotoxemia, gastrointestinal disordersincluding gastrointestinal inflammation, inflammatory bowel disease suchas cecal perforation, intraperitoneal LPS injection, and IBD based onchemically induced colitis, respiratory disorders including sepsis,inflammatory lung injury, acute lung injury, patients subjected tolong-term ventilator therapy and cystic fibrosis, autoimmune diseasessuch as arthritis, dermatomyositis, multiple sclerosis, systemic lupuserythematosus (SLE), celiac disease, chronic fatigue syndrome, Crohn'sdisease, type 1 diabetes, Graves disease, juvenile arthritis, chronicLyme disease, myocarditis, myositis, polymyositis, post-myocardialinfarction syndrome, psoriasis, psoriatic arthritis, reactive arthritis,rheumatic fever, scleroderma, Sjogren's syndrome, thrombocytopenia,ulcerative colitis; neurodegenerative diseases including Alzheimer's,mild cognitive impairment (pre-Alzheimer's), Parkinson's disease,amyotrophic lateral sclerosis (ALS); arthritis including osteoarthritis(OA), arthritic joint inflammation, juvenile idiopathic arthritis (JIA)and serum rheumatoid arthritis (RA); asthma; cancer, includingpancreatic cancer, colorectal cancer, skin cancers including melanoma;cardiac and vessel disease including coronary artery disease (CAD),coronary heart disease, acute coronary, and atherosclerosis, heartfailure; metabolic disorders including type 2 diabetes; β-celltransplantation in diabetes; lung injury and lung related diseasesincluding COPD, pulmonary hypertension, pulmonary fibrosis andpneumonia; Intensive care unit patients being treated for variousconditions including sepsis, systemic inflammatory response syndrome,severe trauma, blunt chest trauma, hemorrhagic shock/trauma, traumaticbrain injury, stroke, spinal cord injury, influenza, chemical toxicity,severe viral or bacterial infections; post-sepsis impairments includingcognitive impairments, persistent splenomegaly, post sepsis anemia;post-surgery neurocognitive disorders; drug induced liver injuryincluding acetaminophen-induced liver injury, ethanol-induced liverdiseases, cryopyrin-associated autoinflammatory syndrome, bleomycininduced lung fibrosis and paracetamol intoxication; nociceptive pain;ischemia (with or without reperfusion), including cardiac ischemia,cerebral ischemia and skeletal muscle ischemia; inflammatory boweldisease; kidney and liver related disease including kidney failure andliver failure, hepatic ischemia/reperfusion injury, acute kidney injury(CHD), chronic kidney disease (CKD), acute liver failure (ALF) includingALF-SIRS and ALF-systemic, liver fibrosis and alcoholic liver disease;trauma/ischemia caused by transplant and graft-versus-host disease;obesity/metabolic syndrome; pancreatitis; pregnancy complication such aspreeclampsia; epilepsy; pulmonary arterial hypertension (PAH); chronicpain; chronic inflammation; chronic inflammatory diseases includingchronic obstructive pulmonary disease (COPD), atherosclerosis andarthritic joint inflammation; and other diseases causing moderate tosevere pain but not limited to post-surgical pain, fever andinflammation of a variety of conditions including rheumatic fever,symptoms associated with influenza or other viral infections, commoncold, low back and neck pain, dysmenorrhea, headache, toothache, sprainsand strains, myositis, neuralgia, synovitis, arthritis, includingrheumatoid arthritis, degenerative joint diseases (osteoarthritis), goutand ankylosing spondylitis, bursitis, burns, and injuries, pepticulcers, gastritis, regional enteritis, ulcerative colitis,diverticulitis or with a recurrent history of gastrointestinal lesions;GI bleeding, coagulation disorders including anemia such ashypoprothrombinemia, hemophilia or other bleeding problems; kidneydisease, chronic fatigue syndrome, traumatic brain injury, concussionand migraines wherein the treatment comprises administering to themammal a therapeutically effective amount of a peptidomimetic smallmolecule modeled after an HMGB1 antagonist tetramer peptide.

Detailed Description of the Preferred Embodiments

The following examples are not meant to be limiting and representcertain embodiments of the present invention.

The experimental testing was designed for robust and unbiased results,with the testing is controlled for the sex, age, and strain of mice.(Yang, H., et al., MD-2 is required for disulfide HMGB1-dependent TLR4signaling, J Exp Med, 2015, 212(1): p. 5-14) Statistical power analysesguided the experiment planning and when possible, commercial reagents(e.g.) that were verified by the supplier were used and the authenticityand purity of specialty reagents made in-house or obtained from otherlaboratories were confirmed through appropriate positive controls andanalytical testing.

More than 2500 publications (Pubmed—http://www.ncbi.nlm.nih.gov) haveused the cecal ligation and puncture model of sepsis since itsintroduction in 1954 (Fojanini, G. and I. Novi, Histological picture ofperitonitis due to ligature of the ceco-appendicular segment of theartificially hibernated animal, Arch. Italian Chir., 1954, 78: p.240-248). The experiments use 20-25 g male Balb/c mice from CharlesRiver, Wilmington, Mass. (Valdés-Ferrer, S. I., et al., High-mobilitygroup box 1 mediates persistent splenocyte priming in sepsis survivors:evidence from a murine model, Shock, 2013, 40(6): p. 492-495). Mice areacclimated for seven days before experiments and observed for anysymptoms or deficiencies that might confound experiments. Assuming areduction in mortality of 50% compared to control, four animals in eachcohort provides 90% statistical power; assuming a reduction of mortalityof 25%, 15 animals in each group provides 90% statistical power. Maleanimals are used; these studies are not powered to include two sexes.

Example 1—Synthesis of K883

In Example 1, K883 (C₁₈H₂₇N₇O₈, having an exact mass of 469.19) wassynthesized in 13 steps; the product of each step was purified, followedby LC-MS to confirm the purity. After purification, compounds werecharacterized by high resolution MS and NMR methods (1H, and 13C). Thesynthetic procedure was as follows:

Commercially available Fmoc-O-tert-butyl-L-serine (1) and Cbz-hydrazine(2) were coupled in the presence of TBTU, HOBt and DIPEA in DMF to formthe Cbz-protected semicarbazide (3) with 90% yield. Fmoc is9-fluorenylmethoxycarbonyl. The Fmoc group of the semicarbazide (3) wasremoved by sodium azide in DMF to yield the free amine (4) (86% yield),which was further elongated with another Fmoc-O-tert-butyl-L-serine (1)in the presence of EDCI, HOBt and DIPEA in DCM to di-SerineCbz-protected semicarbazide (5) (70% yield). After removal of the Fmocgroup with sodium azide in DMF (89% yield), the free amine (6) wascoupled with N-Fmoc-phenyl hydrazine acid chloride (7) in present ofDIPEA in DCM to form the azapeptide (8) in 90% yield. Then the Cbz groupwas de-protected with Pd/C and Et₃SiH in methanol to get thesemicarbazide (9) in 83% yield. Condensations of Fmoc-protectedsemicarbazide (9) with 3-Benzylpropionate aldehyde (10) (Dess Martineoxidation of Benzyl 3-Hydroxypropinonate) to an acyl hydrazone which wasreduced by the catalytic hydrogenation and hydride addition to theprotected aza-tetrapeptide (11) (two steps, 71% yield). CSI thenconverted the amine (11) into the corresponding amide (12) (two steps,60% yield). The Fmoc group was removed with sodium azide in DMF to yieldthe tretra azapeptide (13) (91% yield). De-protection ofO-tert-butyl-L-serine with TFA and O-benzyl with Pd/C and Et₃SiH inmethanol to get the Aza-P5779 (K883) (two steps, 75% yield). There arethirteen reaction steps to the final molecule with the total yield of10%.

To a solution of Cbz-hydrazine (2) (3.0 mmol) andFmoc-O-tert-butyl-L-serine (1) (3.0 mmol) in anhydrous DMF (30 mL) wasadd TBTU (3.6 mmol), HOBt (3.0 mmol) and DIPEA (3.0 mmol). The solutionwas stirred at 25° C. under nitrogen for 15 hrs then concentrated todryness and partitioned between 0.5N HCl (50 mL) and EtOAc (50 mL). Theaqueous layer was extracted with EtOAc (2×50 mL) and the combinedorganic phase were washed with brine (50 mL), dried over Na2SO4,filtered and concentrated to afford the crude product which was purifiedby flash silica gel column chromatography eluting with hexane/EtOAcmixtures to afford the products as a white solids in 90% yield. 1H NMR(500 MHz, CDCl3) δ 8.56 (br, 1H), 7.78 (d, 2H), 7.61 (m, 2H), 7.44-7.28(m, 9H), 6.87 (br, 1H), 5.78 (br, 1H), 5.19 (s, 2H), 4.43-4.37 (m, 3H),4.24 (t, 1H), 3.81 (m, 1H), 3.47 (m, 1H), 1.27 (s, 9H) ppm. 13C NMR (125MHz, CDCl3) δ170.59, 156.32, 156.12, 144.03, 143.81, 141.46, 135.62,128.73, 128.65, 128.58, 128.37, 127.90, 127.24, 125.26, 120.02, 74.85,68.04, 67.35, 61.42, 53.71, 47.24, 27.53 ppm. Mass Spectrum: (ESI) m/z532.40 (M+H)+, m/z 554.40 (M+Na)+.

To a solution of Cbz-protected semicarbazide (3) (5.65 mmol) inanhydrous DMF (30 mL) was added NaN3 (6.78 mmol). The mixture wasstirred at 50° C. under nitrogen for 3 hrs then concentrated to drynessand partitioned between water (50 mL) and EtOAc (50 mL). The aqueouslayer was extracted with EtOAc (2×50 mL) and the combined organic phaseswere washed with brine (50 mL), dried over Na₂SO₄, filtered andconcentrated to afford the crude product which was purified by flashsilica gel column chromatography eluting with hexane/EtOAc/MeOH mixturesto afford the products as a white solids in 86% yield. ¹H NMR (500 MHz,CDCl₃) δ 7.36-7.28 (m, 5H), 6.87 (br, 1H), 5.03 (s, 2H), 3.51-3.48 (m,3H), 1.23 (s, 9H) ppm. ¹³C NMR (125 MHz, CDCl₃) δ172.83, 156.13, 135.80,128.72, 128.51, 128.35, 73.86, 667.87, 67.35, 63.66, 54.87, 27.62 ppm.Mass Spectrum: (ESI) m/z 310.20 (M+H)⁺, m/z 332.20 (M+Na)⁺.

To a solution of Cbz-semicarbazide amine (4) (2.9 mmol) andFmoc-O-tert-butyl-L-serine (1) (3.2 mmol) in anhydrous DCM (50 mL) wasadd EDCI (4.3 mmol), HOBt (0.58 mmol) and DIPEA (2.9 mmol). The solutionwas stirred at 25° C. under nitrogen for 5 hrs then concentrated todryness and partitioned between water (50 mL) and EtOAc (50 mL). Theaqueous layer was extracted with EtOAc (2×50 mL) and the combinedorganic phases were washed with brine (50 mL), dried over Na₂SO₄,filtered and concentrated to afford the crude product which was purifiedby flash silica gel column chromatography eluting with hexane/EtOAcmixtures to afford the products as a white solids in 70% yield. ¹H NMR(500 MHz, CDCl₃) δ 8.82 (br, 1H), 7.80 (d, 2H), 7.63 (d, 2H), 7.44-7.28(m, 9H), 7.18 (br, 1H), 6.71 (br, 1H), 5.83 (br, 1H), 5.17 (s, 2H), 4.62(br, 1H) 4.42 (d, 2H), 4.28-4.23 (m, 2H), 3.93 (m, 1H), 3.82 (m, 1H),3.48 (m, 2H), 1.24 (s, 18H) ppm. ¹³C NMR (125 MHz, CDCl₃) δ170.17,170.02, 156.21, 155.95, 144.00, 143.81, 141.47, 141.44, 135.74, 128.68,128.50, 128.35, 127.91, 127.25, 125.28, 120.18, 75.30, 74.42, 67.90,67.41, 62.08, 60.80, 60.58, 54.95, 53.03, 47.24, 27.52 ppm. MassSpectrum: (ESI) m/z 675.13 (M+H)⁺, m/z 692.07 (M+Na)⁺.

To a solution of Cbz-protected di-serine semicarbazide (5) (2.49 mmol)in anhydrous DMF (10 mL) was added NaN3 (3.02 mmol). The mixture wasstirred at 50° C. under nitrogen for 3 hrs then concentrated to drynessand partitioned between water (25 mL) and EtOAc (25 mL). The aqueouslayer was extracted with EtOAc (2×25 mL) and the combined organic phaseswere washed with brine (25 mL), dried over Na₂SO₄, filtered andconcentrated to afford the crude product which was purified by flashsilica gel column chromatography eluting with hexane/EtOAc mixtures toafford the products as a white solids in 89% yield. Mass Spectrum: (ESI)m/z 453.20 (M+H)⁺, m/z 475.33 (M+Na)⁺.

To a solution of Cbz-protected di-serine semicarbazide amine (6) (2.44mmol) and N-Fmoc-phenyl hydrazine acid chloride (7) (2.44 mmol) inanhydrous DCM (24 mL) at 0° C. was added DIPEA (2.44 mmol). The solutionwas stirred and warmed to 25° C. under nitrogen for 5 hrs thenconcentrated to dryness and partitioned between water (50 mL) and EtOAc(50 mL). The aqueous layer was extracted with EtOAc (2×50 mL) and thecombined organic phases were washed with brine (50 mL), dried overNa₂SO₄, filtered and concentrated to afford the crude product which waspurified by flash silica gel column chromatography eluting withhexane/EtOAc mixtures to afford the products as a white solids in 90%yield. ¹H NMR (500 MHz, CDCl₃) δ 8.93 (br, 1H), 7.80 (d, 2H), 7.54 (d,2H), 7.44 (t, 2H), 7.35-7.31 (m, 12H), 7.18 (br, 2H), 6.63 (br, 1H),6.48 (br, 1H) 6.32 (br, 1H), 5.16 (s, 2H), 4.62 (m, 1H) 4.53 (m, 2H),4.36 (m, 1H), 4.20 (m, 1H), 3.91 (m, 1H), 3.80 (m, 1H), 3.49 (m, 2H),1.20 (s, 18H) ppm. ¹³C NMR (125 MHz, CDCl₃) δ170.65, 169.92, 157.26,155.90, 155.88, 155.21, 143.27, 143.18, 141.37, 135.62, 135.53, 129.00,128.51, 128.29, 128.14, 128.06, 127.95, 127.20, 124.93, 120.12, 74.94,74.12, 67.70, 61.97, 60.70, 54.76, 52.92, 50.77, 46.96, 27.38 ppm.

To a solution of Cbz-protected di-serine semicarbazide (8) (2.05 mmol)in anhydrous MeOH (10 mL) was added 10% Pd/C (340 mg) followed by Et₃SiH(20.5 mmol). The mixture was stirred at 25° C. under nitrogen for 20mins then filtered through a pad of celite and concentrated to drynessand partitioned between water (50 mL) and EtOAc (50 mL). The aqueouslayer was extracted with EtOAc (2×50 mL) and the combined organic phaseswere washed with brine (50 mL), dried over Na₂SO₄, filtered andconcentrated to afford the crude product which was purified by flashsilica gel column chromatography eluting with hexane/EtOAc mixtures toafford the products as a white solids in 83% yield. ¹H NMR (500 MHz,CDCl₃) δ 8.26 (br, 1H), 7.79 (d, 2H), 7.54 (d, 2H), 7.44 (t, 2H),7.35-7.28 (m, 5H), 7.18 (m, 2H), 6.99 (br, 1H), 6.39 (br, 1H), 6.48 (br,1H) 6.30 (d, 1H), 4.50 (m, 3H), 4.37 (m, 1H), 4.20 (m, 1H), 3.91 (m,1H), 3.82 (m, 1H), 3.49-3.39 (m, 2H), 1.26 (s, 9H), 1.18 (s, 9H) ppm.¹³C NMR (125 MHz, CDCl₃) δ170.73, 170.64, 157.26, 155.34, 143.44,143.38, 141.59, 135.75, 129.14, 129.08, 128.27, 128.15, 127.39, 125.09,120.31, 75.18, 73.99, 67.95, 62.34, 61.11, 54.80, 53.18, 50.77, 47.21,27.61, 27.58 ppm.

To a solution of protected di-serine semicarbazide (9) (0.87 mmol) and3-Benzylpropionate aldehyde (10) (2.62 mmol) in anhydrous ethanol (6 mL)was added acetic acid (24 uL). The solution was stirred at 25° C. undernitrogen for 2 hrs then concentrated to dryness. The crude productre-dissolved in anhydrous MeOH (20 mL) and added NaCNBH₃ (4.35 mmol)followed by acetic acid (4.35 mmol). The mixture was stirred at 55° C.under nitrogen for 15 hrs then concentrated to dryness and partitionedbetween water (50 mL) and EtOAc (50 mL). The aqueous layer was extractedwith EtOAc (2×25 mL) and the combined organic phases were washed withbrine (25 mL), dried over Na₂SO₄, filtered and concentrated to affordthe crude product which was purified by flash silica gel columnchromatography eluting with hexane/EtOAc mixtures to afford the productsas a white solids in 71% yield (two steps). ¹H NMR (500 MHz, CDCl₃) δ8.43 (br, 1H), 7.80 (d, 2H), 7.54 (d, 2H), 7.44 (t, 2H), 7.36-7.31 (m,10H), 7.17 (br, 2H), 7.01 (br, 1H), 6.30 (br, 2H), 5.12 (s, 2H), 4.52(m, 3H), 4.33 (m, 1H), 4.21 (t, 1H), 3.91 (m, 1H), 3.81 (m, 1H), 3.42(m, 2H), 3.14 (t, 2H), 2.56 (t, 2H), 1.22 (s, 9H), 1.17 (s, 9H) ppm. ¹³CNMR (125 MHz, CDCl₃) δ 172.08, 170.59, 169.75, 157.38, 143.40, 143.35,141.56, 136.00, 135.64, 129.13, 129.09, 128.69, 128.41, 128.37, 128.27,128.13, 127.37, 125.08, 125.07, 120.30, 75.10, 73.96, 67.91, 66.54,62.20, 61.11, 60.60, 54.94, 53.23, 50.78, 47.34, 47.15, 32.82, 27.58ppm. Mass Spectrum: (ESI) m/z 851.33 (M+H)⁺, m/z 873.40 (M+Na)⁺.

To a solution of the protected aza-tetrapeptide amine (11) (0.70 mmol)in anhydrous THF (5 mL) at 0° C. was added chlorosulfonyl (CSI) (0.84mmol) rapidly. The solution was stirred at 0° C. under nitrogen for 1 hrthen water added (5 mL). The solution was warmed to room temperaturethen concentrated and partitioned between water (25 mL) and EtOAc (25mL). The aqueous layer was extracted with EtOAc (2×15 mL) and thecombined organic phases were washed with brine (25 mL), dried overNa₂SO₄, filtered and concentrated to afford the crude product which waspurified by flash silica gel column chromatography eluting withhexane/EtOAc mixtures afford the products as a white solids in 60% yield(two steps). ¹H NMR (500 MHz, CDCl₃) δ 9.05 (br, 1H), 7.70 (d, 2H), 7.43(d, 2H), 7.34 (t, 2H), 7.24-7.21 (m, 10H), 7.06 (m, 4H), 6.68 (br, 1H),6.30 (br, 1H), 5.14 (br, 2H), 4.47 (m, 1H), 4.34 9 m, 2H), 4.13 (m, 1H),4.09 (m, 2H), 3.82 (m, 2H), 3.76 (m, 2H), 3.63 (m, 2H), 3.51 (m, 1H),3.45 (m, 2H), 3.23 (t, 2H), 1.08 (s, 18H) ppm. ¹³C NMR (125 MHz, CDCl₃)δ 172.10, 170.56, 169.75, 157.36, 157.34, 143.40, 143.35, 141.57,136.03, 136.65, 129.14, 129.09, 128.70, 128.41, 128.37, 128.28, 128.14,127.38, 125.08, 120.31, 75.12, 73.96, 69.94, 66.52, 62.23, 61.13, 54.86,53.24, 50.78, 47.36, 47.10, 32.92, 27.47 ppm. Mass Spectrum: (ESI) m/z894.40 (M+H)⁺, m/z 916.47 (M+Na)⁺.

To a solution of protected aza-tetrapeptide amide (12) (0.48 mmol) inanhydrous DMF (5 mL) was added NaN3 (0.72 mmol). The mixture was stirredat 50° C. under nitrogen for 2 hrs then concentrated to dryness for andpartitioned between water (5 mL) and EtOAc (5 mL). The aqueous layer wasextracted with EtOAc (2×5 mL) and the combined organic phases werewashed with brine (5 mL), dried over Na₂SO₄, filtered and concentratedto afford the crude product which was purified by flash silica gelcolumn chromatography eluting with hexane/EtOAc/MeOH mixtures to affordthe products as a white solids in 91% yield. Mass Spectrum: (ESI) m/z672.47 (M+H)⁺, m/z 694.33 (M+Na)⁺.

To a solution of aza-tetrapeptide amide (13) (0.43 mmol) in anhydrousMeOH (5 mL) was added 10% Pd/C (58 mg) followed by Et₃SiH (4.3 mmol).The mixture was stirred at 25° C. under nitrogen for 20 mins thenfiltered through a pad of celite and concentrated to dryness. The acidwas used directly for next step. Mass Spectrum: (ESI) m/z 582.20 (M+H)⁺,m/z 604.27 (M+Na)⁺.

The crude acid (0.43 mmol) was dissolved in 10 mL TFA at 0° C. then wasstirred and warmed to 25° C. under nitrogen for 1 hr. After concentratedto dryness, the crude product was purified by flash silica gel columnchromatography eluting with CHCl3/MeOH (4:1 v/v) mixture to afford theAza-P5779 (K883) as a white solids in 75% yield (two steps). ¹H NMR (600MHz, CDCl₃) δ 7.3-7.30 (m, 5H), 4.69 (s, 2H), 4.40 (t, 1H), 4.36 (t,1H), 3.98 (dd, 1H), 3.95 (dd, 1H), 3.85 (dd, 1H), 3.82 (dd, 1H), 3.80(br, 2H), 2.48 (t, 2H) ppm. ¹³C NMR (125 MHz, CDCl3) δ178.10, 173.33,170.83, 160.27, 159.81, 136.77, 128.67, 128.07, 127.52, 62.31, 61.21,56.63, 55.42, 52.80, 44.88, 34.91 ppm. Mass Spectrum: (ESI) m/z 470.00(M+H)⁺, m/z 492.07 (M+Na)⁺.

Example 2—Stability of K883

In Example 2, the stability of K883 is compared to that of the peptideP5779. P5779 is the peptide that corresponds to K883 prior toreplacement of α-carbon atoms with α-nitrogen atoms. The in vitrostability of P5779 and K883 were tested in mouse serum; residualcompound was monitored at a wavelength of 210 nm and sampled at 0 hours,3 hours and 6 hours. The initial concentration of the P5779 and K883were both 100 μg. The results are depicted in FIG. 14, with FIGS.14A-14F showing the relative stability measured by HPLC of the peptideP5779 and the enhanced stability of K883 versus P5779 as tested in mouseserum. Thus, K883 displayed a significant stability profile and 95% ofthe material survived upon incubation in mouse sera compared to 25% ofcompound P5779 (FIGS. 14A-14F).

Example 3—Bioavailability and Administration

In Example 3, the bioavailability and optimal route of administrationfor K883 is determined. K883 is poorly soluble in water (<100 μg/ml) andhas, to date, been dissolved in dimethyl sulfoxide (DMSO), which hasbeen associated with cytotoxicity even at low concentrations (deMenorval M A., Effects of dimethyl sulfoxide in cholesterol-containinglipid membranes: a comparative study of experiments in silico and withcells, PLoS One, 2012; 7(7):e41733; Galvao J, Unexpected low-dosetoxicity of the universal solvent DMSO, FASEB J, 2014; 28(3):1317-30;Hanslick J L, Dimethyl sulfoxide (DMSO) produces widespread apoptosis inthe developing central nervous system, Neurobiol Dis., 2009; 34(1):1-10;Notman R, Molecular basis for dimethylsulfoxide (DMSO) action on lipidmembranes, J Am Chem Soc., 2006; 128(43):13982-3). Preliminary evidencesuggests that K883 is soluble to >5 mg/ml in a mixture containingPBS:PEG 300:propylene glycol:polysorbate 80 at 50:40:5:5, which areacceptable excipients to the FDA. This provides the basis for developingintravenous (IV) formulation that will serve as a benchmark fordeveloping oral (PO) formulations.

The testing is controlled for the sex, age, and strain of mice.Statistical power analyses guide experiment planning. When possible,commercial reagents (e.g. antibodies and synthesized peptides) that areverified by the supplier are used and the authenticity and purity ofspecialty reagents made in-house or obtained from other laboratories byincluding appropriate positive controls and analytical testing.

Numerous published studies from major influenza labs have failed toreveal a sex difference in lethality following influenza infection,consistent with statistical analysis of the inventors of WT male vs.female responses to PR8 infection. Female mice are typically used asmales are more aggressive and fight, leading to inflammation that canconfound interpretations. Power analysis indicates that fivemice/treatment, (two experimental replicates=10 mice in total), issufficient to detect a 40% difference for 2 samples with repeatedmeasures with α=0.05 and power=0.88.

In Example 3, an acceptable oral formulation for animal and human dosingis developed and is assessed for solubility using a standardflocculation assay in blood; PO formulations are tested by incubationwith simulated stomach acid. K883 stability is confirmed by LC-MS.Formulations exhibiting >1 mg/ml solubility will be advanced tobioavailability testing.

For each formulation, at least two cohorts of rats are dosed with K883either intravenously (IV) or with one of the oral (PO) formulations. Forthe IV cohort, rats are administered 1 mg/kg K883; for the first POcohort of each new formulation, rats are administered 10 mg/kg to enabledetection of as low as 10% bioavailability. For all cohorts, bloodsamples are collected at baseline (immediately prior to K883administration) and at 15, 30, 60, 90, 120, 180, 240, 360 and 480minutes post-administration; PO cohorts have an additional samplecollected at 600 minutes post-administration. Plasma concentrations ofK883 are determined by LC-MS/MS; the detection threshold using thismethod is 0.5 ng/ml. Next, bioavailability is estimated for eachformulation. If the bioavailability for any of the PO formulations isestimated at >25%, the experiment is repeated using a PO dose of 1mg/kg, equivalent to the IV dose. Pharmacokinetics parameters arederived using WinNonlin (v6.4) software using a non-compartmental model.The maximum plasma concentrations (CO) after IV dosing and the plasmahalf-life (t/2) are estimated. The area under the time-concentrationcurve (AUC) is computed using the linear trapezoidal rule withcalculation to the last quantifiable data point. Clearance (CL) iscalculated from dose/AUC. Steady state volume of distribution (Vss) iscalculated from CL*MRT (mean residence time). Samples below the limit ofquantitation (0.5 ng/mL) are treated as zero for pharmacokinetic dataanalysis.

In the event that none of the oral formulations show adequatebioavailability for use in subsequent in vivo testing, in vivo testsdescribed in Example 2 using only intravenously administered K883 areconducted.

Example 4—Efficacy of K883

In Example 4 and in Example 17 (below), the efficacy of K883 forrescuing survival in a mouse model of sepsis and for mitigating thepersistent anemia observed in sepsis survivors is evaluated. The HMGB1antagonists are synthesized and purified according to Examples 1 and 2.K883 will be evaluated for rescuing mortality and reducing anemiafollowing cecal ligation and puncture. Inhibiting the interactionbetween HMGB1 and MD-2 with the peptide antagonist P5779 rescued cecalligation and puncture-associated mortality compared to an inactivecontrol peptide. (Yang, H., et al., MD-2 is required for disulfideHMGB1-dependent TLR4 signaling, J Exp Med, 2015, 212(1): p. 5-14). Theseexperiments test the efficacy of K883, which persists incirculation >12-fold longer than P5779, for enhancing survival followingcecal ligation and puncture. (See Example 17 and FIG. 25 discussedbelow)

In survival studies, wild-type mice are randomly assigned to one of sixgroups to undergo either sham surgery (n=10) or cecal ligation andpuncture to induce sepsis. One cecal ligation and puncture cohort (n=30)receives no treatment and serves as the negative control; the remainingfour cecal ligation and puncture cohorts (30 mice each) receive one ofthe following interventions: K883 (500 g/mouse) or vehicle is deliveredby tail vein injection, or K883 (500 g/mouse) or vehicle delivered byoral gavage. Doses are administered daily for four days starting 24 hrpost-surgery. Doses and timing are based on previous studies with thepeptide antagonist. (Yang, H., et al., MD-2 is required for disulfideHMGB1-dependent TLR4 signaling, J Exp Med, 2015, 212(1): p. 5-14); theinterval may be adjusted upon evaluation of pharmacokinetics data forK883. Mice are observed for seven days to determine survival rates foreach group.

In anemia studies, wildtype mice are randomly assigned to one of threegroups to undergo either sham surgery (120 mice) or cecal ligation andpuncture to induce sepsis. The “negative control” cecal ligation andpuncture cohort (120 mice) receive no treatment; the remaining cecalligation and puncture cohort (120 mice) are given K883 (500 g/mouse) ondays 2-5 via the more effective route identified above. Starting at day9, survivors from the cecal ligation and puncture+treatment cohort areevenly divided and randomly assigned to two groups. The first receiveK883 (500 g/mouse) on days 9-11; the second receive daily doses of K883(500 g/mouse) on days 9-28. Dosing interval may be modified oncepharmacokinetics data are available. For each group, at 5-day intervalsstarting on day 11, 6 survivors are sacrificed and blood collected bycardiac puncture for CBC analysis to measure hematocrit (Hct) andhemoglobin (Hgb) levels. Interferon (IFN) signatures and HMGB1 levelsare also determined. (Valdes-Ferrer, S. I., et al., HMGB1 mediatesanemia of inflammation in murine sepsis survivors, Mol Med, 2015). Atday 31, all remaining survivors are sacrificed for blood collection.

Example 5—K883 Inhibition of MD-2 Binding to HMGB1

In Example 5, the ability of K883 to inhibit HMGb1 binding to MD-2 isevaluated in an in vitro protein/protein interaction assay using humanproteins.

FIGS. 12A and 12B show the inhibition of MD-2 binding to HMGB1 asmeasured by SPR binding the inhibition of MD-2 binding to HMGB1 asmeasured by SPR binding studies using a Biacore T200® instrument withthe inhibition achieved with P5779 shown in FIG. 12A and thedose-responsive inhibition achieved with increasing concentrations ofK883 (1-2000 nM) shown in FIG. 12B. In FIG. 12A, MD-2 held constantthroughout assay at 500 nM, concentration of P5779 varied (2×) from 2000nM to 0 nM, IC50 is around 68.5 nM inhibition of HMGB1 binding to MD2.In FIG. 12B, MD-2 is held constant throughout assay at 500 nM,concentration of K883 varied (2×) from 2000 to 0 nM and IC50 is around90 nM. Both compounds were very comparable in inhibiting HMGb1: MD2complex formation which is a critical step for HMGb1 proinflammatorysignaling pathway.

Inhibiting HMGb1 and MD2 is a critical step in HMGb1 proinflammatorysignaling pathway. P5779 has been previously identified first as aninhibitor of HMGb1:MD2 complex formation in Surface Plasmon Resonance(SPR) binding studies and consequently was examined in multiple meurinemodels of inflammation and has been shown to be protective (Yang, H., etal., MD-2 is required for disulfide HMGB-dependent TLR4 signaling, J ExpMed, 2015, 212(1): p. 5-14; ______

-   -   Both compounds are shown in Example 5 to be very comparable in        inhibiting HMGb1: MD2 complex formation. This is a first step in        validating that the modification in the sequence of P5779 to        azapetide does not alter the affinity toward MD2 and inhibition        of the HMGb1:MD2 complex formation.

Example 6—K883 Inhibition of HMGB1-Induced TNF Release

In Example 6, the ability of K883 to inhibit HMGB1-induced TNF releasein human and mouse macrophages was evaluated. As discussed above, TNF isan early effector of inflammation. Drugs intended to antagonize earlyeffectors of inflammation, such as TNFα (tumor necrosis factor), wereineffective due to the early and short therapeutic window (Anti-tumornecrosis factor therapy in sepsis: update on clinical trials and lessonslearned, Crit Care Med, 2001, 29(7 Suppl): p. S121-5) and possiblyharmful. HMGB1, however, is a late mediator of inflammation.

FIGS. 15A-15C are graphical depictions of the inhibition of HMB1-inducedtumor necrosis factor (TNF) secretion in both human and mousemacrophages. In the studies of FIGS. 15A and 15B, mouse primarymacrophages in 96 well plate were stimulated with HMGB1 (1 μg/ml), plusincreasing amounts of P5779 or K883 (0.1, 1 and 10 uM) for 16 hours. Inthe study of FIG. 15C, human primary macrophages in 96 well plate werestimulated with HMGB1 (1 μg/ml), plus increasing amounts of K883 (0.1, 1and 10 uM) for 16 hours. For all of these studies, TNF released wasmeasured using an ELISA. The data shown in the Figures are means+SEM(n=4-5). *: P<0.05 vs. HMGB1.

FIG. 15A shows the inhibition achieved with increasing concentrations ofK883 (0-10 μM) in human primary macrophages and FIG. 15B shows theinhibition achieved with P5779 (0-10 μM) in human primary macrophages.FIG. 15C shows the inhibition achieved with increasing concentrations ofK883 (0-50 μM) of HMGB1-induced TNF secretion from mouse macrophages. Inboth human and mouse macrophages, K883 significantly inhibits TNFrelease with an IC₅₀ of 1 uM while similar inhibition with P5779 wasachieved at 10 uM. The potency of K883 over P5779 is due in part tostability as described above.

Example 7—K883 does not Inhibit PAMPs-Induced TNF Release in HumanMacrophages

In Example 7, K883 is evaluated for inhibition of PAMPs-induced TNFrelease in human macrophages. The selectivity of K883 toward HMGb1 andnot other PAMPs such as LPS, PGN, AGE and Poly I:C was assessed bymeasuring the TNF release in human macrophages after exposure to theabove PAMPS in the presence of compound K883. In the studies of FIG. 15,human primary macrophages in 96 well plate were stimulated with HMGB1 (1μg/ml), TLR4-agonist LPS at 4 ng/ml, TLR3 agonist poly I:C at 50 μg/ml,TLR2 agonist peptidoglycan (PGN) at 5 μg/ml and RAGE agonist S100A12 at50 μg/ml plus increasing amounts of K883 for 16 hours. TNF released wasmeasured. Data shown in the Figures are means+SEM (n=4-5). *: P<0.05 vs.HMGB1.

The results demonstrate the selectivity of compound K883 toward HMGB1(FIGS. 15A-C) since it failed to inhibit other PAMPS (FIG. 16A-D).

Example 8—K883 does not Inhibit DAMPs-Induced TNF Release in HumanMacrophages

In Example 8, the ability of K883 to inhibit DAMPs-induced TNF releasein human macrophages was evaluated. As discussed above, compound K883was selective toward HMGB1 in inhibiting TNF release. In the studies ofFIGS. 16A-D, human primary macrophages in 96 well plate were stimulatedwith HMGB1 (1 μg/ml), TLR4-agonist LPS at 4 ng/ml, TLR3 agonist poly I:Cat 50 μg/ml, TLR2 agonist peptidoglycan (PGN) at 5 μg/ml and RAGEagonist S100A12 at 50 μg/ml plus increasing amounts of K883 for 16hours. TNF released was measured. Data shown are means+SEM (n=4-5). *:P<0.05 vs. HMGB1. The data of FIGS. 16A-D demonstrate that K883 does notinhibit other PAMPs (LPS, PGN, AGE and Poly I:C).

Example 9—K883 does not Inhibit DAMPs-Induced TNF Secretion

The experiments of FIGS. 17A-G test ability of K883 to inhibitDAMPs-induced TNF secretion. TNF is an early effector of inflammation.Drugs intended to antagonize early effectors of inflammation, such asTNFα (tumor necrosis factor), were ineffective due to the early andshort therapeutic window (Anti-tumor necrosis factor therapy in sepsis:update on clinical trials and lessons learned, Crit Care Med, 2001, 29(7Suppl): p. S121-5) and possibly harmful. HMGB1, however, is a latemediator of inflammation.

In the experiments of FIGS. 17A-G, human primary macrophages on 96-wellculture plates (105 cell/well) were stimulated with HMGB1 (1 μg/ml),CIRP (cold-induced RNA binding protein, 1 μg/ml), SAA (serum amyloid A,5 μg/ml), PEDF (pigment epithelial derived factor, 5 μg/ml), HSP 70(heat shock protein 70, 1 μg/ml), HSP90 (heat shock protein 90, 1 μg/ml)or H2A (histone 2A, 5 μg/ml) plus increasing amounts of K883 asindicated for 16 hours. TNF released was measured by ELISA. *: P<0.05vs. HMGB1 alone. N=5 experiments.

FIGS. 17A-G show that K883 causes inhibition of HMGB1-induced TNFsecretion (FIG. 17A) but TNF secretion induced by other DAMPs (FIG.17B-G) is not inhibited by various concentrations of K883 in humanmacrophages.

Example 10—P5779 Peptide Enhances Survival in Cecal Ligation andPuncture-Sepsis and Reduces Liver Injury in Ischemia/Reperfusion Model

The proinflammatory role of HMGb1 has been well established in multipleanimal models and in this application, we examined the efficacy ofinhibiting circulating HMGb1 by K883 in two mouse models (sepsis (nodata) and liver injury). Previously, Yang H, MD-2 is required fordisulfide HMGB1-dependent TLR4 signaling, J Exp Med., 2015; 212(1):5-14)showed that P5779 was protective in these two models as seen below.

FIGS. 18, 19 and 20A are all directed to comparative data for compoundP5779. P5779 protects against sepsis lethality induced by cecal ligationand puncture (CLP) in male C57BL/6 mice. In the comparative experimentof Example 11, P5779 (at 50 or 500 μg/mouse) or scrambled controlpeptide (500 μg/mouse) was given IP once a day for 4 days starting at 24hours post CLP surgery. Survival was monitored for 2 weeks. *: P<0.05vs. control peptide group. n=20 mice/group. FIG. 18 shows that P5779peptide enhanced percentage survival in cecal ligation andpuncture-sepsis.

Example 11—Treatment with HMGB1 Inhibitor P5779 AmelioratesAPAP-Mediated Toxicity

FIGS. 19A to 19F show effects of treatment with P5779 on amelioratingAPAP-mediated toxicity such as inflammation, lethality, and tissuedamage in a mouse model of APAP-induced liver injury. FIGS. 19A-D depictthe serum inflammatory markers, AST (FIG. 19A), ALT (FIG. 19B, TNF (FIG.19C), and HMGB1 (FIG. 19D) after P5779 treatment.

In the comparative experiment of FIG. 19A, after overnight fasting, maleC57BL/6 mice received APAP injection (IP, 350 mg/kg) plus P5779 (at 50or 500 μg/mouse) or scrambled control peptide (500 μg/mouse, IP injectedat 2 and 7 hours post-APAP) and mice were euthanized at 24 hourspost-APAP. n=6-10 mice per group. Besides serum measurements, H&E imagesof livers from APAP-injected mice showed reduced liver necrosis (arrow)in mice received P5779 compared to scrambled control peptide-treatedgroup. Clinical scores were assessed based on the amount of necrosis andinflammation (Methods). Percent survival (2 weeks) post-APAP (400 mg/kg)was significantly improved in mice received treatment of P5779 (500μg/mouse, IP once a day for 5 days starting at 2 hours post-APAPinjection) n=30 mice in each group. *: P<0.05 vs. control peptide group.

In the comparative experiment of FIG. 19B, administration of P5779ameliorates tissue damage in warm liver ischemia and reperfusion (I/R)in male C57BL/6 mice. P5779 (or vehicle control) was administeredintraperitoneally at 500 μg/mouse at the time of I/R surgery andeuthanized 6 hours later. Serum levels of ALT and AST were reduced inP5779-treated group vs. vehicle controls. *: P<0.05 vs. I/R group. n=5-7mice/group.

Images of liver H&E staining (6 hours after reperfusion) showed reducedinflammation in P5779-treated mice as compared to vehicle control(neutrophil infiltration, arrow). n=3-5 mice per group. FIG. 19E showsincreased survival after treatment with P5779 but not control scramblepeptide, while FIG. 19F depicts histology images showing treatment withHMGB1 inhibitor P5779 reduced APAP-mediated liver injury.

Example 12—K883 Reduces APAP-Induced Liver Injury: Histology

HMGb1 has been implicated in sterile injury and blocking HMGb1 by eitheranti-HMGb1 or P5779 has been shown to be efficacious as evident byimproving survival, reducing elevated liver enzymes due to injury andreducing liver damage/necrosis as evident by histology. (Yang, H., etal., MD-2 is required for disulfide HMGB1-dependent TLR4 signaling, JExp Med, 2015, 212(1): p. 5-14).

FIGS. 21A to 21C show histology images demonstrating that K883 reducesAPAP-Induced liver injury in the mouse model. In the experiment of FIGS.21A-C, after overnight fasting, male C57BL/6 mice received APAPinjection (IP, 350 mg/kg) plus K883 (at 50 μg/mouse, IP injected at 2and 7 hours post-APAP) and mice were euthanized at 24 hours post-APAP.n=6-10 mice per group. Besides serum measurements, H&E images of liversfrom APAP-injected mice showed reduced liver necrosis (arrow) in micereceived K883 compared to vehicle treated group. Clinical scores wereassessed based on the amount of necrosis and inflammation. FIG. 21A is ahistology obtain from a control mouse (not treated with APAP). In FIG.21B, necrosis is evident in the histology in response to APAP. Necrosiswas resolved in APAP-treated mouse upon administration of K883.

Example 13—K883 Improved APAP-Induced Survival in Mice

In the experiment of FIG. 22, mice (n=15 in each group) were treatedwith APAP (400 mg/kg) to induce liver damage and lethality. The groupthat received K883 showed significant improvement measured by percentsurvival (2 weeks) post-APAP over the control group with 14 mice out of15 surviving the toxicity of APAP when treated with K883. (50 μg/mouse,IP once-a-day for 5 days starting at 2 hours post-APAP injection)compared to 8 in the control group. *: P<0.05 vs. control peptide group.

Thus, FIG. 22 shows improved survival outcome in mice that have beenadministered K883 in the APAP-induced liver injury model.

Example 14—PK/PD, Dosing and Formulation

FIGS. 20A and 20B shows that K883 is effective at a lower dose thanP5779 in APAP model. FIG. 20A shows serum inflammatory markers afterP5779 treatment in the APAP-liver toxicity model, 500 ugs/mouse led tosignificant reductions in ALT and FIG. 20B is a graphical depictionshowing that treatment with 50 ugs/mouse of K883 reduced serum ALT inthe liver APAP-toxicity model when compared to vehicle controls. P<0.05vs. I/R group. n=5-7 mice/group.

Images of liver H&E staining (6 hours after reperfusion) showed reducedinflammation in K883-treated mice as compared to vehicle control(neutrophil infiltration, arrow). n=3-5 mice per group are seen in FIGS.21A-C.

Example 15—Stability of P5779 in Mice Serum

In FIG. 23, the pharmacokinetics of K883 and P5779 was assessed by LC-MSupon intravenous administration of 1 mg/kg of each compound. Bothcompounds were dissolved in 100 mM of PBS. Following IV administrationto rats, the plasma half-life of P5779 was <1 minute while for K883 itwas 1.2+/−0.2 hours (n=3 animals/experiment).

Where Example 2 shows that P5779 inhibits HMGB binding to MD2 usingSurface Plasmon Resonance (SPR), in the present Example, it can be seenthat K883 also has a similar inhibitory effect. The in-vitro and in-vivohalf-lives of K883 and P5779 were measured. The in-vitro half-life ofK883 was greater than 15 hours (FIG. 14A-F), while the in-vitrohalf-life of the native peptide P5779 was 60 minutes. The in-vivohalf-life of K883 was greater than 69 min, while the in-vivo half-lifeof the native peptide P5779 was less than 1 min. The results areprovided in Tables 2 and 3 below. The data of Tables 2 and 3 are alsoplotted in FIG. 23.

TABLE 2 Individual and Average Plasma Concentrations (ng/ml) for FSSEafter Intravenous Administration at 1 mg/KG in Male Sprague-Dawley ratsIntravenous (1 mg) Rat # Time (hr) 970 971 972 Mean SD 0 (pre-dose) BLOQBLOQ BLOQ ND ND 0.017 BLOQ BLOQ BLOQ ND ND 0.033 BLOQ BLOQ BLOQ ND ND0.083 BLOQ BLOQ BLOQ ND ND 0.167 BLOQ BLOQ BLOQ ND ND 0.25 BLOQ BLOQBLOQ ND ND 0.33 BLOQ BLOQ BLOQ ND ND 0.50 BLOQ BLOQ BLOQ ND ND AnimalWeight 0.284 0.271 0.281 0.279 0.007 (kg) Volume Dosed 0.28 0.27 0.280.28 0.01 (mL) C₀ (ng/mL)¹ ND ND ND ND ND t_(max) (hr)¹ ND ND ND ND NDt_(1/2)(hr) ND ND ND ND ND MRT_(last) (hr) ND ND ND ND ND CL (L/hr/kg)ND ND ND ND ND V_(ss) (L/kg) ND ND ND ND ND AUC_(last) ND ND ND ND ND(hr · ng/mL) AUC_(ss) ND ND ND ND ND (hr · ng/mL)

TABLE 3 Individual and Average Plasma Concentrations (ng/ml) for K883after Intravenous Administration at 1 mg/KG in Male Sprague-Dawley RatsIntravenous (1 mg/kg) Rat # Time (hr) 973 974 975 Mean SD 0 (pre-dose)BLOQ BLOQ BLOQ ND ND 0.25 4360 4240 3830 4143 278 0.50 3020 2500 32202913 372 1.0 814 1160 1300 1091 250 1.5 281 258 280 273 13.0 2.0 133 130142 135 6.24 4.0 17.0 15.1 17.7 16.6 1.35 6.0 6.49 4.04 4.77 5.10 1.268.0 2.01 0.871 1.68 1.52 0.586 Animal 0.288 0.282 0.281 0.284 0.004Weight (kg) Volume 0.29 0.28 0.28 0.28 0.01 Dosed (mL) C₀ (ng/mL)¹ 62957191 4556 6014 1340 t_(max) (hr)¹ 0 0 0 0 0 t_(1/2)(hr) 1.30 0.972 1.181.15 0.165 MRT_(last) (hr) 0.535 0.528 0.606 0.556 0.0430 CL (L/hr/kg)0.265 0.263 0.267 0.265 0.00200 V_(ss) (L/kg) 0.144 0.139 0.163 0.1490.0127 AUC_(last) 3772 3807 3749 3776 29.4 (hr · ng/mL) AUC_(ss) 37763808 3751 3778 28.5 (hr · ng/mL)

Example 16—K883 Increases the Survival of Flu Virus Infected MiceCompared with P5779 Peptide

Mice were infected with mouse-adapted influenza virus, strains A/PR/8/34intranasally (i.n.) (PR8; ˜7500 TCID₅₀, 25 μl/nares) or maCa.04 (˜2200TCID₅₀, i.n.). K883 is a small molecule inhibitor of HMGB1 that wasshown recently to prevent MD-2/HMGB1 interaction and block HMGB1-inducedTLR4 signaling, while not interfering with LPS-inducedcytokine/chemokine induction. K883 protected mice against hepaticischemia/reperfusion injury, APAP chemical toxicity, and sepsis. Toassess the efficacy of K883 in influenza infection, WT C57BL/6J micewere infected with PR8 and, two days later mice were treatedintraperitoneally with either vehicle or with K883 (100 ug/mouse) for 5consecutive days. Survival and clinical scores were monitored daily for14 days. (5-10 mice/treatment group/experiment). K883 treated miceshowed significant survival and lowered clinical scores, while micetreated with the vehicle showed higher clinical scores and succumbed toinfection (FIG. 24). As shown in FIG. 24, K883, an HMGB1 antagonist,blocks influenza-mediated lethality.

Example 17—K883 Enhances Survival in Cecal Ligation and Puncture-Sepsis

The proinflammatory role of HMGb1 was examined by evaluating theefficacy of inhibition of circulating HMGb1 by K883 in a sepsis. Asdiscussed above (see e.g. Example 10), Yang H, MD-2 is required fordisulfide HMGB1-dependent TLR4 signaling, J Exp Med., 2015; 212(1):5-14)showed that P5779 was protective in these two models.

As seen in FIG. 25, K883 protects against sepsis lethality induced bycecal ligation and puncture (CLP) in male C57BL/6 mice. In thecomparative experiment of Example 18, K883 (at 500 μg/mouse) or vehicle(control) was given IP once a day for 3 days starting at 24 hours postCLP surgery. Survival was monitored for 2 weeks. *: P<0.05 vs. controlpeptide group. n=15 mice/group. FIG. 25 shows that K883 enhancedpercentage survival in cecal ligation and puncture-sepsis.

Example 18—Evaluation of Therapeutic Potential of K883 for ReducingInfluenza-Induced ALI in Mice

When administered daily for five days, starting two days post-infection,the peptide P5779 rescues lethality in a mouse model ofinfluenza-induced ALI. (Shirey K A, Novel strategies for targetinginnate immune responses to influenza, Mucosal Immunol, 2016;9(5):1173-82). Example 5 ascertains the efficacy of K883 for the sameindication, using P5779 as a positive control.

Three in vivo studies are conducted, each comprising two independentreplicate experiments. For each experiment, cohorts of mice are treatedwith K883, the peptide P5779, or vehicle following intranasal infectionwith a lethal dose of influenza, strain A/PR/8/34. Previous experimentshave shown that experimental cohorts of five mice (i.e., 10mice/cohort/study) yield sufficient statistical power to infer treatmenteffects. (Shirey K A, Novel strategies for targeting innate immuneresponses to influenza, Mucosal Immunol., 2016; 9(5):1173-82; Shirey KA, The TLR4 antagonist Eritoran protects mice from lethal influenzainfection, Nature, 2013; 497(7450):498-502). For the survival andhistology/serology studies, the cohorts are the following: 1-P5779, 500μg in IV vehicle delivered intraperitoneally on days 2-6 post-infection(positive control); 2-IV vehicle (no treatment); 3-Gavage vehicle (notreatment); 4-K883, dose 1 delivered intravenously on days 2-6post-infection; 5-K883, 5×(dose 1) delivered intravenously on days 2-6post-infection; 6-K883, dose 1 delivered by oral gavage on days 2-6post-infection; 7-K883, 5×(dose 1) delivered by oral gavage on days 2-6post-infection. “Dose 1” will be determined based on bioavailability andPK.

As a survival study, six- to eight-week old wildtype C57BL/6J mice areinfected with the mouse-adapted influenza strain PR8 intranasally aspreviously described. (Shirey K A, Novel strategies for targeting innateimmune responses to influenza, Mucosal Immunol., 2016; 9(5):1173-82;Shirey K A, The TLR4 antagonist Eritoran protects mice from lethalinfluenza infection, Nature, 2013; 497(7450):498-502). Starting on thesecond day post-infection and continuing through day 6, mice are treatedaccording to their cohort. Mice are monitored daily for survival, weightloss, and clinical signs of illness (e.g., lethargy, piloerection,ruffled fur, hunched posture, rapid shallow breathing, and audiblecrackling). Mice receive a clinical score ranging from 0 (no symptoms)to 5 (moribund) daily; mice scoring a 5 on two consecutive days will beeuthanized. Mice are observed for 14 days, at which point survivors areeuthanized.

For study of histology/serology, infection and treatment are performedas in the survival study. On day 7 post-infection, all surviving miceare euthanized to collect serum by cardiac puncture, bronchoalveolarlavage fluid (BALF, from one lung), and tissue samples for histologicaland serological analysis (from the contralateral lung). Samples arecollected and then analyzed. Levels of HMGB1 in serum and BALF aredetermined using a commercially available ELISA test. In addition, thelevels of the pro-inflammatory signals TNFα (tumor necrosis factor) andsoluble RAGE in BALF are measured. (37-40). (Raucci A, A soluble form ofthe receptor for advanced glycation endproducts (RAGE) is produced byproteolytic cleavage of the membrane-bound form by the sheddase adisintegrin and metalloprotease 10 (ADAM10), FASEB J., 2008;22(10):3716-27; Uchida T, Receptor for advanced glycation end-productsis a marker of type I cell injury in acute lung injury, Am J Respir CritCare Med., 2006; 173(9):1008-15; van Zoelen M A, Receptor for advancedglycation end products is detrimental during influenza A viruspneumonia, Virology, 2009; 391(2):265-73; Zhang L, Receptor for advancedglycation end products is subjected to protein ectodomain shedding bymetalloproteinases, J Biol Chem., 2008; 283(51):35507-16). Forhistopathology, fixed sections of paraffin-embedded lungs are stainedwith hematoxylin and eosin. Slides are randomized and blinded, thenscored for tissue damage and inflammation, necrosis, apoptosis, andinnate immune cell infiltration.

Assuming K883 rescues lethality in the survival studies, the therapeuticwindow is studied by defining the time interval post-infection when K883offers protection. For this study, the optimal K883 dose (IV or PO)determined by the survival studies is administered to the experimentalcohorts on subsequent days following infection. The control cohort aretreated with vehicle starting on the third day post-infection;experimental cohorts are treated with K883 on days 3-6, days 4-6, days 5and 6, or only day 6 post-infection. Mice are monitored daily forsurvival and scored as described above for clinical illness.

High-resolution structural studies and molecular docking modelling areconducted to visualize binding between K883 and MD-2/TLR4, as previouslyreported for P5779. (Yang H, MD-2 is required for disulfideHMGB1-dependent TLR4 signaling, J Exp Med., 2015; 212(1):5-14). Asecondary risk is that mice will react adversely to repeated dosing withK883. This concern is substantially mitigated by the observation thatK883 has been well-tolerated in single-dose studies with rats.Furthermore, the survival study features high- and low-dose treatmentwith K883 by two routes of administration. It is expected that at leastone of these four configurations will indicate a regimen conducive totreating with K883. If mice even in the low-dose cohorts have an adversereaction, however, the survival study with low-dose K883 treatment willfirst be repeated only on alternate days rather than daily. In case thisstrategy does not resolve the problem, the dose of K883 will be halvedand the survival study will be repeated.

Example 19—the Effect of HMGB1 in Sciatic Nerve (CCI) Model

In Example 19, the effect of HMGB1 in sciatic nerve (CCI) model isevaluated in rats that have undergone CCI compared to untreated rats.

As seen in FIG. 26, disulfide HMGB1 levels in spinal cord are elevatedin CCI model in rats. Disulfide HMGB1 induces neuropathic pain(mechanical allodynia) in rat paws in a time dependent manner (data notshown). As shown in FIG. 26, this effect can be partially reversed byneutralizing anti-HMGB1 antibody (mAb) 2g7 which amelioratesHMGB1-induced mechanical allodynia. (N=6-8 rats/group. *, **: p<0.05)These results indicated that selective HMGB1 isoforms are critical forthe development of mechanical hypersensitivity. Furthermore, in theCCI-induced chronic pain model. (Bennett G. J., A peripheralmononeuropathy in rat that produces disorders of pain sensation likethose seen in man, Pain, 1988; 33(1): 87-107), elevated HMGB1 levels inspinal cord were reported. (Wan W., The emerging role of HMGB1 inneuropathic pain: a potential therapeutic target for neuroinflammation,Journal of Immunology research, (2016); He Z., Intrathecallentivirus-mediated transfer of interleukin-10 attenuates chronicconstriction injury-induced neuropathic pain through modulation ofspinal high-mobility group box 1 in rats, Pain Physician, 2012; 16(5):E615-625). Administration of K883 ameliorated both mechanical andthermal hypersensitivity.

Example 20—Effect of Selective HMGB1-TLR4/MD-2 Inhibition on NeuropathicPain

Example 20 determines the effect of selective HMGB1-TLR4/MD-2 inhibitionon reduction of neuropathic pain in sciatic nerve (CCI) model rats.

Twenty-four male Wistar rats were separated into four groups (n=6/group)for treatment as follows [please give details concerning each of thefour groups regarding procedure and treatment:

Group I: CCI

Group II: Normal

Group III CCI+PBS (phosphate-buffered saline) vehicle control (PBS)

Group IV CCI+=K883 (800 μg/rat) or vehicle control (PBS) wasadministered after CCI as an IP injection once daily for three days.

The CCI rats each received surgery. The K883 and were evaluated for 2weeks afterward. In FIGS. 27A and 27B, the groups are listed as CC K883(800 μg/rat) or vehicle control was given as IP injection once daily forthree days. Mechanical and thermal sensitivity tests were also performedover time. Hargreaves Thermal Hypersensitivity test was administered tothe rats as well as Von Frey mechanical hypersensitivity test. Theresults of this testing can be seen in FIGS. 27A and 27B which show theeffects of the repeated K883 administration on CCI-induced neuropathicpain (*: P<0.05 vs. CCI PBS group N=6 rats/group). These resultsindicate that rats did not develop tolerance to repeated treatment ofK883 during the short period of time.

Example 21—Effect of Selective HMGB1-TLR4/MD-2 Inhibition in STZ-InducedDiabetes

In Example 21, the effect of selective HMGB1-TLR4/MD-2 inhibition inSTZ-induced diabetes was evaluated. Increased levels of HMGB1 have beenreported in both diabetic patients and animal models. For example,elevated expression of HMGB1 is found in the retinas of diabeticpatients and rat models with retinopathy. (Pachydaki S. I., Upregulationof RAGE and its ligands in proliferative retinal disease, ExperimentalEye Research, 2006; 82(5): 807-815; Yu Y., The role of high mobilitygroup box 1 (HMGB-1) in the diabetic retinopathy inflammation andapoptosis, International Journal of Clinical and Experimental Pathology,2015; 8(6): 6807). Moreover, elevated serum HMGB1 levels were seen indiabetic patients. (Dasu M. R., Increased toll-like receptor (TLR)activation and TLR ligands in recently diagnosed type 2 diabeticsubjects, Diabetes Care, 2010; 33(4): 861-868) and rats withhyperglycemia. (Hagiwara S., Effects of hyperglycemia and insulintherapy on high mobility group box 1 in endotoxin-induced acute lunginjury in a rat model, Critical Care Medicine, 2008; 36(8): 2407-2413;Skrha Jr J, Relationship of soluble RAGE and RAGE ligands HMGB1 andEN-RAGE to endothelial dysfunction in type 1 and type 2 diabetesmellitus, Experimental and Clinical Endocrinology & Diabetes, 2012;120(05): 277-281). Based on this literature, tests were conducted on theeffects of P5779 and K883 on STZ-induced diabetes in mice.

Mice were administered repetitive administration of K883 (500 μg/mouse).The results of the testing is seen in FIGS. 28A-C, which show that K883is beneficial in STZ-induced diabetes. Repetitive administration of K883was therefore shown to be beneficial in STZ-induced diabetes. Comparedto AI5779 or PBS controls, treatment with K883 delays hyperglycemia andimproves weight gain, and reduces insulitis in STZ-diabetic mice. (*:P<0.05 vs. PBS group. N=6-8 mice per group).

Example 22—Design of K883 Derivatives to Improve Oral Bioavailability

Rationale: Although K883 has a better pharmacokinetic profile comparedto P5779 (t1/2>60 min versus <5 min), it has low oral bioavailability.It was initially hypothesized that the poor bioavailability might be dueto the acid liability of the amide bond between the two serine residuesupon exposure to the gastric fluid. To address this concern, K883 wasincubated under acidic conditions (pH=2) for two hours and the stabilitywas monitored over time by LC-MS. The conclusion of this stabilitytesting was that K883 was resistant to acid hydrolysis. In order toimprove the oral bioavailability K883, different formulations of K883will be tested for improved absorption, followed by new PK studies ofthe most attractive oral formulations. In parallel to this testing, K883will be further optimized in order to generate multiple derivatives toimprove its absorption followed by new PK studies of the most attractivederivative to determine the oral bioavailability.

Binding (SPR) and computational studies were conducted with an initiallead peptide. Based on this testing, it was learned that: 1) theglutamate of the P5779 peptide is required to form hydrogen bonds withMD-2 and TLR4 residues (H bonds and salt bridges are formed between theglutamate residue and Arg264, Asp339 (TLR4) and Tyr102, Glu92 (MD-2));2) the phenyl moiety of the phenylalanine is anchored in the hydrophobicpocket of MD-2 and substitution of the phenyl moiety by fluorobiphenylbinds better due to multiple pi-pi stacking; 3) replacing serine byasparagine generates an elegant set of hydrogen bonds with the backboneof MD-2 (Tyr102, Glu92 and Va193; and 4) optimization of a linker(—CH2CH2-) that fits well between the biphenyl moiety and the azapeptideof asparagine-glutamate. These findings will be used to synthesize aspecific, potent and orally bioavailable inhibitor of HMGB1:MD-2: TLR4complex formation by translating and integrating the known chemicalinformation concerning P5779 and K883 into a new class with moreattractive pharmacokinetics due to the improve stability of theserine-serine amide bond in P5779 and K883.

Building the Class of Compounds:

Compounds were identified using binding and computational and synthesismethods. Based on the results, the aryl system was identified as anattractive moiety to anchor in the hydrophobic pocket of MD-2. Shownbelow is the proposed synthesis of Class A compounds, with the Rpharmacores discussed above. As seen below, the aryl systems arepropionic acid-based derivatives that can be coupled in the final stageto the fully protected moiety of Asp-Glu(aza) peptide.

The next objective was to restrict the flexibility of glutamic acidwhile preserving the selectivity and binding affinity toward MD-2. Toaddress this objective, Class B were identified based on substitutingthe glutamic acid residue with pyrrolidin-2-ones (g-lactams), aka asL-proline, 4-amino-5-oxo. Shown below is the proposed synthesis of ClassB compounds, with the R pharmacores shown above.

This building block can serve as an isostere of aspartic and glutamicacid. Previously, it has been shown that incorporation of such units isadvantageous and improved the stability and bioavailability compared toparent peptides. (Abell A., Advances in amino acid mimetics andpeptidomimetics, Elsevier; Vol. 2, 1999), and the stereoselectivesynthesis of these isomers has been well documented and they arecommercially available. The computational study demonstrated that theseunits should provide the expected interaction with TLR4 and MD-2, but toa lesser extent compared to class A.

In vitro permeability (Caco2 cells) and human microsomal stabilitystudies will next be conducted to predict the oral bioavailability ofthese K883 derivatives. The outcome of these studies will supportcontinued development of an oral formulation of K883 derivative or mayindicate that an alternative route of administration (e.g. subcutaneous)may be preferable. It is expected that the docking and molecular dynamicsimulations of the newly developed K883 derivatives will be similar toK883. In vitro permeability and microsomal stability data will beobtained for both parent K883 and K883 derivatives. The outcome of thesestudies will support continued development of an oral formulation ofK883 derivative. However, the therapeutic effects of K883 derivativesare likely dependent on the tissue distribution. Thus, future studieswill evaluate the oral bioavailability and tissue distribution of themost promising K883 derivative.

Example 23—Pharmacokinetics of K883 Following SubcutaneousAdministration

Rationale: Subcutaneous administration route is often used formanagement of diabetes treatment. To determine whether subcutaneousadministration route is suitable for K883, K883 will be subcutaneouslyadministered into healthy minipigs, after which the PK parameters willbe defined.

Design: K883 will be subcutaneously administered into healthy minipigs,after which the PK parameters will be defined. Plasma samples will becollected for analysis immediately prior to dosing and at 15, 30, 60 and90 minutes and 2, 4, 8, 12, and 24 hr after the dose and analyzed todetermine the concentration of K883 using LC-MS.

Expected outcomes and alternative approaches: The outcome of thesestudies will support the decision to continue development of an SCformulation of K883, along with the results of the oral bioavailabilitystudies of the molecules to be synthesized in.

Example 24—Efficacy of Selective HMGB1-TLR4/MD-2 Inhibition in a RodentModel of DPN

Rationale: Recent research on diabetic neuropathy has been focused onthe changes in the interactions between the nervous system and theimmune system that occur in parallel with glial cell activation. Severalanimal models have been used to study the underlying mechanisms for thiscomplication. Some commonly used animal models include STZ-induced ratand mouse models. Even though the manifestations of diabetic neuropathicpain vary, impaired neurotrophism and proinflammatory responses havebeen identified in the development of diabetic neuropathic pain. Thus,as a proof-of-concept study in this Phase I project, the efficacy ofselective HMGB1-TLR4/MD-2 inhibition in a rat (male and female) model ofSTZ-induced diabetic neuropathy will be tested.

In Example 24, the efficacy of intravenously administered K883 in rat(male and female) model of streptozotocin (STZ)-induced diabeticneuropathy will be tested. Pain behavior tests, weight change and bloodglucose levels will be recorded. At the end of experiment, the rats willbe euthanized so that their pancreas, DRG, spine and blood can beassessed for histological changes, chemokine and cytokines levels,immune and physiological responses.

Design: A well-established rodent model of diabetes and DPN80, theSTZ-DPN model, will be used to evaluate efficacy. This STZ-DPN modelmirrors clinical type 1 diabetes in humans. (Kitada M., Rodent models ofdiabetic nephropathy: their utility and limitations, InternationalJournal of Nephrology and Renovascular Disease, 2016; 9: 279). Afterevaluation of the results of this testing, a positive result were leadto further evaluation of other types of diabetes DPN models (i.e. type 2diabetes). Rats (Sprague-Dawley, 150-180 gm, male and female) willsubject to low dose of STZ (50 mg/kg) IP injection once a day for 5 daysto induce diabetes and DPN. The regimen of multiple injection of lowdose STZ is chosen to minimize the non-specific toxicity of STZ to otherorgans besides pancreas (Id.), and is also based on observations that itwill induce diabetes (see FIG. 29) and will induce DPN. (Zhao X.,Inhibition of CaMKIV relieves streptozotocin-induced diabeticneuropathic pain through regulation of HMGB1, BMC Anesthesiology, 2016;16(1): 27; Kitada M., Rodent models of diabetic nephropathy: theirutility and limitations, International Journal of Nephrology andRenovascular Disease, 2016; 9: 279; Akbar S., 6-Methoxyflavanoneattenuates mechanical allodynia and vulvodynia in thestreptozotocin-induced diabetic neuropathic pain, Biomedicine &Pharmacotherapy, 2016; 84: 962-971). Animals will receive K883 orcontrol peptide injected daily intravenously (via implanted jugular veincatheter) for 2 weeks starting at 2 weeks after STZ administration. K883treatment in this STZ model in mice was beneficial as revealed bydiabetic parameters (preliminary data, FIG. 29). This time frame waschosen as DPN was observed starting 2 weeks after STZ administration andlast till 8 weeks in rodents. (Id.) Three logarithmic doses of K883 orcontrol peptide (0, 8, 80 or 800 μg/rat/day) will be included to coverboth effective and non-effective doses of K883 based on previous resultsachieved with STZ and CCI pain models (FIGS. 28 and 29). Pain behaviortests, weight change and blood glucose levels will be recorded duringthat time.

At the end of the 2-week treatment, animals (10 per group) will beeuthanized so that pancreas, DRG (dorsal root ganglion), spine and bloodcan be assessed for histological changes, chemokine and cytokineslevels, immune and physiological responses. The following are the listof animal groups and tests/assays that will be performed in this study.

Animal groups: The study will use eight groups of rats per sex, witheach group having 10 rats. (80 female rats and 80 male rats) as follows:Group 1: normal rats.

Groups 2-4: STZ rats with K883 treatment (doses of 8, 80 and 800ug/rat/day).

Groups 5-7: STZ rats with control peptide treatment.

Group 8: STZ rats with PBS (vehicle) treatment.

Total=8 groups per sex (male or female).

In previous studies of K883 in the CCI rat model, it was observed thatin vehicle-treated control rats with neuropathic pain, paw withdrawaloccurred at 3.73+/−0.58 (SD) seconds compared to 5.45+/−0.98 seconds inrats treated with K883. Assuming in the STZ model that a similardifference (1.6 seconds) is found, with SD of 1.0, then to achieve 90%power at the alpha=0.05 level, 5 animals per group are required. As thiswill be the first study of the effects of K883 in the STZ diabetesmodel, 10 animals per group will be used to account for lesserdifference between groups or larger SD.

Tests/Assays:

1. Body weight and blood glucose levels (via tail vein) over time.2. Allodynia assessment: mechanical, thermal hypersensitivity (both heatand cold) assessment over time.3. Histology of pancreas: insulitis score.4. Serum measurements: insulin, glucagon (diabetes parameters), HMGB1,CXCL1, TNF, IL-6 and IL-1B (inflammation markers)5. DRG and spine: HMGB1, CXCL1, TNF, IL-6 and IL-1B (inflammationmarkers). Could be squeezed to save room.

Expected Outcomes and Alternative Approaches:

Previous studies demonstrated that K883 specifically blocks disulfide(cytokine-inducing) HMGB1-mediated inflammation and does not block theimmune integrity to PAMPs. It is therefore expected that intravenousadministration of K883 will dose-dependently reduce mechanical andthermal hypersensitivity in rats with STZ-induced DPN. Intravenousadministration route was chosen for a proof-of-concept study to avoidissues concerning the low oral bioavailability of K883. As the onlyknown selective HMGB1-TLR4/MD-2 inhibitor, using K883 will provide vitalinformation about the effects of selective HMGB1-TLR4/MD-2 inhibition onpainful DPN. As preferred administration routes for diabetic patientsare oral and subcutaneous routes, future studies will expand thesefindings by using novel K883 derivatives with improved oralbioavailability or a preferred subcutaneous formulation of parent K883.

Example 25—Disulfide HMGB1-Induced Calcium Influx in F11 Cells

K883 is shown to inhibit disulfide hmgb1-induced calcium influx in F11cells in FIGS. 30A-30E. These studies all measured relative fluorescentintensity with FIG. 30C which included the largest amount of K883 (50μg/ml) having the most inhibition of disulfide HMGB1.

Example 26—CCI-Induced Thermal and Mechanical Hypersensitivity

The effect of K883 on CCI-induced thermal and mechanicalhypersensitivity over time in rats was assessed. Rats (male Wistar,150-180 gm, n=6/group) had CCI surgery. K883 (800 μg/rat) or vehiclecontrol (PBS) was given as IP injection once a day for 3 days. Two weeksafter surgery, thermal (Hargreaves) or mechanical (von Frey)hypersensitivity was assessed. *: P<0.05 vs. PBS group. As seen in FIGS.31A and 31B, K883 improved CCI-induced thermal and mechanicalhypersensitivity over time in rats.

Example 27—CCI-Induced CXCL1 and TNF Expression (DRGs)

K883 is shown to reduce CCI-induced CSCL1 and TNF expression (DRGs)FIGS. 32A-32C.

Example 28—CCI-Induced CXCL1, TNF and IL-1β Expression (Spine)

K883 is shown to reduce CCI-induced CSCL1, TNF and IL-1β expression(Spine) in FIGS. 33A-33D.

Example 29—Novel HMGB1-Mediated Neurobioloical Mechanism

Dorsal root ganglia (DRG) sensory neurons are selectively activated bydisulfide HMGB1-induced Ca2+ influx as seen from FIG. 34. Calcium is anessential intracellular mediator in neurons, and Ca2+ influx increases10-100 fold when neuron is activated57-60. Preliminary studies haveshown that exposure to disulfide HMGB1 in rat primary DRGs (cell body ofsensory nociceptors) stimulated calcium influx, and HMGB1 mAb 2g7reverses the effects in vitro. This novel mechanism may be anotheruntapped target for therapeutic intervention of DPN.

Example 30—Selective HMGB1-TLR-4/MD2 Inhibition Reduces Neuropathic Painin CCI Rats

HMGB1 (disulfide and fully reduced) induces neuropathic pain (mechanicalallodynia) in rat paws (FIG. 35A) in a time dependent manner (data notshown). This effect can be partially reversed by anti-HMGB1 mAb 2g7treatment (FIG. 35B). These results indicated that selective HMGB1isoforms are critical for the development of mechanicalhypersensitivity. Furthermore, in the CCI-induced chronic pain model(Bennett G J, Xie Y-K, A peripheral mononeuropathy in rat that producesdisorders of pain sensation like those seen in man, Pain, 1988;33(1):87-107, 71), elevated HMGB1 levels in spinal cord have beenreported. (Wan W, et al., The emerging role of HMGB1 in neuropathicpain: a potential therapeutic target for neuroinflammation, Journal ofImmunology Research. 2016; 2016.27, 72; He Z, et al., Intrathecallentivirus-mediated transfer of interleukin-10 attenuates chronicconstriction injury-induced neuropathic pain through modulation ofspinal high-mobility group box 1 in rats, Pain Physician, 2012;16(5):E615-625) Administration of HMGB1 mAb 2g7 or HMGB1 specificinhibitor K883 ameliorated the thermal hypersensitivity (Table 4).

TABLE 4 Paw Withdrawal Latency (sec) NO CCI (Hours post treatment)Treatment CCI 0 2 6 24 mAb2g7 9.5 ± 1.0 4.1 ± 1.0  7.1 ± 1.0*  6.4 ±0.6* 5.6 ± 0.4 K883 9.5 ± 1.0 4.1 ± 1.0 4.3 ± 1.2  6.0 ± 0.6* 5.0 ± 0.5Vehicle 9.5 ± 1.0 4.1 ± 1.0 4.0 ± 0.5 3.7 ± 0.2 4.6 ± 0.7 *P < 0.05 vs.0 hr.

In this experiment, male Wistar rats (n=6/group) had CCI surgery. K883(800 μg/rat) or 2g7 (300 μg/rat) or vehicle control was given as IPinjection 30 minutes prior to disulfide HMGB1 injection to the hindpaw.Mechanical allodynia was assessed 5 hours later. N=6-8 rats/group. *:p<0.05) vs. HMGB1 alone. Mechanical and thermal sensitivity tests werealso performed over time. In these experiments, K883 (800 μg/rat) orvehicle control was given as IP injection once daily for three days.After 2 weeks, the results indicated that rats did not develop toleranceto repeated treatment of K883 during the short period of time. FIG. 35Ashows that HMGB1 induces mechanical allodynia in rats. *: p<0.05) vs.PBS and FIG. 35B mAb 2g7 ameliorates HMGB1-induced mechanical allodyniain rats.

CONCLUSION

In the preceding specification, the invention has been described withreference to specific exemplary embodiments and examples thereof. Itwill, however, be evident that various modifications and changes may bemade thereto without departing from the broader spirit and scope of theinvention as set forth in the claims that follow. The specification anddrawings are accordingly to be regarded in an illustrative manner ratherthan a restrictive sense.

What is claimed is:
 1. A method of treating and/or inhibiting severesepsis in a mammal comprising administering to a mammal atherapeutically effective amount of a peptidomimetic small moleculemodeled after an HMGB1 antagonist tetramer peptide.
 2. The method ofclaim 1, wherein the peptidomimetic small molecule is an HMGB1antagonist tetramer peptide which has been stabilized with at least oneazatide linkage.
 3. The method of claim 2, wherein the peptidomimeticsmall molecule is a modified P5779 wherein at least one terminal peptidebond has been replaced with an azatide linkage.
 4. The method of claim2, wherein the peptidomimetic small molecule peptidomimetic smallmolecule is a modified P5779 wherein the terminal peptide bonds havebeen replaced with azatide linkages.
 5. The method of claim 2, whereinthe peptidomimetic small molecule is K883.
 6. The method of claim 1,wherein the mammal is a human.
 7. The method of claim 1, wherein themethod of administration is selected from the group consisting of oraldelivery, parenteral delivery, buccal delivery, sublingual delivery,nasal delivery, inhalation delivery, nebulization delivery, topicaldelivery, transdermal delivery and suppository delivery.
 8. The methodof claim 10, wherein the modified P5779 is K883.
 9. A method oftreatment, comprising treating a mammal for a disease or conditionselected from the group consisting of non-influenza pulmonaryinfections, smoke or toxic gas inhalation, gastric acid aspiration,transfusion reactions, reactions and injuries caused by mechanicalventilation arthritis, colitis, sterile ischemia, traumatic injury,cancer and infection, hemorrhagic shock, endotoxemia, gastrointestinaldisorders including gastrointestinal inflammation, inflammatory boweldisease such as cecal perforation, intraperitoneal LPS injection, andIBD based on chemically induced colitis, respiratory disorders includingsepsis, inflammatory lung injury, acute lung injury, patients subjectedto long-term ventilator therapy and cystic fibrosis, autoimmune diseasessuch as arthritis, dermatomyositis, multiple sclerosis, systemic lupuserythematosus (SLE), celiac disease, chronic fatigue syndrome, Crohn'sdisease, type 1 diabetes, Graves disease, juvenile arthritis, chronicLyme disease, myocarditis, myositis, polymyositis, post-myocardialinfarction syndrome, psoriasis, psoriatic arthritis, reactive arthritis,rheumatic fever, scleroderma, Sjogren's syndrome, thrombocytopenia,ulcerative colitis; neurodegenerative diseases including Alzheimer's,mild cognitive impairment (pre-Alzheimer's), Parkinson's disease,amyotrophic lateral sclerosis (ALS); arthritis including osteoarthritis(OA), arthritic joint inflammation, juvenile idiopathic arthritis (JIA)and serum rheumatoid arthritis (RA); asthma; cancer, includingpancreatic cancer, colorectal cancer, skin cancers including melanoma;cardiac and vessel disease including coronary artery disease (CAD),coronary heart disease, acute coronary, and atherosclerosis, heartfailure; metabolic disorders including type 2 diabetes; β-celltransplantation in diabetes; lung injury and lung related diseasesincluding COPD, pulmonary hypertension, pulmonary fibrosis andpneumonia; Intensive care unit patients being treated for variousconditions including sepsis, systemic inflammatory response syndrome,severe trauma, blunt chest trauma, hemorrhagic shock/trauma, traumaticbrain injury, stroke, spinal cord injury, influenza, chemical toxicity,severe viral or bacterial infections; post-sepsis impairments includingcognitive impairments, persistent splenomegaly, post sepsis anemia;post-surgery neurocognitive disorders; drug induced liver injuryincluding acetaminophen-induced liver injury, ethanol-induced liverdiseases, cryopyrin-associated autoinflammatory syndrome, bleomycininduced lung fibrosis and paracetamol intoxication; nociceptive pain;ischemia (with or without reperfusion), including cardiac ischemia,cerebral ischemia and skeletal muscle ischemia; inflammatory boweldisease; kidney and liver related disease including kidney failure andliver failure, hepatic ischemia/reperfusion injury, acute kidney injury(CHD), chronic kidney disease (CKD), acute liver failure (ALF) includingALF-SIRS and ALF-systemic, liver fibrosis and alcoholic liver disease;trauma/ischemia caused by transplant and graft-versus-host disease;obesity/metabolic syndrome; pancreatitis; pregnancy complication such aspreeclampsia; epilepsy; pulmonary arterial hypertension (PAH); chronicpain; chronic inflammation; chronic inflammatory diseases includingchronic obstructive pulmonary disease (COPD), atherosclerosis andarthritic joint inflammation; and other diseases causing moderate tosevere pain but not limited to post-surgical pain, fever andinflammation of a variety of conditions including rheumatic fever,symptoms associated with influenza or other viral infections, commoncold, low back and neck pain, dysmenorrhea, headache, toothache, sprainsand strains, myositis, neuralgia, synovitis, arthritis, includingrheumatoid arthritis, degenerative joint diseases (osteoarthritis), goutand ankylosing spondylitis, bursitis, burns, and injuries, pepticulcers, gastritis, regional enteritis, ulcerative colitis,diverticulitis or with a recurrent history of gastrointestinal lesions;GI bleeding, coagulation disorders including anemia such ashypoprothrombinemia, hemophilia or other bleeding problems; kidneydisease, chronic fatigue syndrome, traumatic brain injury, concussionand migraines wherein the treatment comprises administering to themammal a therapeutically effective amount of a peptidomimetic smallmolecule modeled after an HMGB1 antagonist tetramer peptide.
 10. Amethod of treating or inhibiting adverse conditions relating to surgeryor the administration of anticoagulants, comprising administering to themammal a therapeutically effective amount of a peptidomimetic smallmolecule modeled after an HMGB1 antagonist tetramer peptide prior to thesurgery or the administration of the anticoagulants.
 11. The method ofclaim 5, wherein the K883 is combined with an excipient comprisingPBS:PEG 300:propylene glycol:polysorbate 80 at 50:40:5:5.
 12. The methodof claim 7, wherein the therapeutically effective amount is orallyadministered to the mammal.
 13. The method of claim 7, wherein thetherapeutically effective amount is intravenously administered to themammal.
 14. The method of claim 7, wherein the mammal is human.
 15. Themethod of claim 8, wherein the method of administration is selected fromthe group consisting of oral delivery, parenteral delivery, buccaldelivery, sublingual delivery, nasal delivery, inhalation delivery,nebulization delivery, topical delivery, transdermal delivery andsuppository delivery.
 16. The method of claim 3, wherein the modifiedP5779 is stable for greater than 60 minutes in plasma or simulatedstomach acid.
 17. The method of claim 3, wherein the aqueous solubilityof the modified P5779 is greater than about 1 mg/ml.
 18. The method ofclaim 10, wherein the peptidomimetic small molecule is a modified P5779wherein at least one terminal peptide bond has been replaced with anazatide linkage.
 19. The method of claim 10, wherein the peptidomimeticsmall molecule peptidomimetic small molecule is a modified P5779 whereinthe terminal peptide bonds have been replaced with azatide linkages. 20.The method of claim 10, wherein the peptidomimetic small molecule isK883.